AT-Profile Timing Belts (AT3, AT5, AT8, AT10, AT15, AT20)

Q: What is an AT-profile timing belt?

A modified metric trapezoidal belt with wider tooth base for higher load. AT stands for Advanced Trapezoidal. Six pitches: AT3 (3mm) through AT20 (20mm). Polyurethane only with steel or Kevlar cord.

Q: Can I use AT-profile belts on T-profile pulleys?

No. AT and T pulleys have different groove widths even at the same pitch. Mixing causes poor engagement and belt failure. Always match belt profile to pulley profile.

Q: What is the difference between AT-profile and HTD?

AT uses modified trapezoidal teeth; HTD uses curvilinear. Both provide higher load than standard trapezoidal but through different designs. Different pulleys, never interchangeable even at same pitch.

Q: Which AT pitch is most popular?

AT10 for heavy applications (especially linear motion gantries). AT5 for lighter precision automation. Together they account for the majority of AT orders.

Q: Are AT-profile belts available in open-end form?

Yes. All six pitches available in open-end polyurethane with steel or Kevlar cord. Industry standard for European linear motion.

Q: Are AT-profile belts available in neoprene?

No. AT-profile is polyurethane only. For neoprene at similar pitches, consider T-profile or HTD, but changing profile requires changing pulleys.

Q: Are AT-profile belts food-grade?

Available in FDA-compliant polyurethane grades meeting FDA 21 CFR 177.2600 and EU 10/2011. Most commonly specified at AT5 and AT10.

Q: Does Texas Belting stock all AT pitches?

Yes. AT3 through AT10 commonly stocked with same-day shipping. AT15 and AT20 are specialty with longer lead times on some sizes. Call 888-203-2358.

2655 products

AT-Profile Timing Belts (AT3, AT5, AT8, AT10, AT15, AT20)

AT-profile timing belts are the high-performance evolution of the European T-profile system. The "AT" stands for Advanced Trapezoidal. AT-profile belts feature a modified tooth design with a wider base and optimized root geometry that distributes stress more evenly across the tooth, significantly increasing load capacity and reducing the risk of tooth shear compared to standard T-profile belts at the same pitch.

The AT-profile family spans six pitches from 3mm to 20mm, covering applications from compact precision servo drives to the largest industrial gantry systems. AT-profile belts are manufactured exclusively from polyurethane with steel wire or Kevlar tensile cords, and are available in both closed-loop and open-end (continuous roll) form. Open-end AT-profile belts with steel cord are the industry standard for European-designed heavy linear motion systems. Texas Belting stocks AT-profile timing belts across all six pitches.

AT-profile family overview:
Tooth form: Modified trapezoidal (wider base, optimized root geometry)
Standard: European (evolution of DIN T-profile)
Pitches: AT3 (3mm), AT5 (5mm), AT8 (8mm), AT10 (10mm), AT15 (15mm), AT20 (20mm)
Material: Polyurethane only (steel cord standard, Kevlar available)
Open-end: Available in all six pitches
FDA/food contact: Available in FDA-compliant polyurethane grades
Related family: T-profile (standard version, lower load capacity, different pulleys)

Need AT-profile timing belts?

Tell us the pitch, part number, or application. We will confirm AT vs T profile and provide pricing and availability across all six AT pitches.

Request a Quote 888-203-2358

AT-Profile Pitch Comparison

The six AT-profile pitches cover the full range from compact precision drives to the heaviest belt-driven positioning systems. Each pitch has a dedicated page with detailed specifications, part number decoders, width guides, and FAQs.

Profile	Pitch	Load Class	Common Widths	Typical Applications
AT3	3mm	Light to moderate	6 to 16mm	Precision servo drives, miniature linear motion, medical instruments
AT5	5mm	Moderate to heavy	6 to 50mm	Linear motion, European automation, packaging, printing
AT8	8mm	Heavy	10 to 75mm	Heavy linear motion, large gantries, CNC routers
AT10	10mm	Very heavy	16 to 100mm	Industry standard for heavy gantries, CNC, waterjet, heavy automation
AT15	15mm	Extreme	25 to 150mm	Largest gantry systems, stone processing, bridge crane positioning
AT20	20mm	Maximum	50 to 150mm	Absolute heaviest belt-driven positioning. Specialty pitch.

AT10 is the most widely specified AT-profile pitch, serving as the workhorse for heavy linear motion and industrial positioning. AT5 is the most popular for precision automation and lighter linear motion. AT15 and AT20 are specialty pitches for the most extreme loads.

AT-Profile vs. T-Profile: Why the AT Upgrade?

The AT-profile was developed to overcome the load capacity limitations of the standard T-profile. By widening the tooth base and optimizing the root geometry, AT-profile belts can carry significantly more load per tooth without increasing the belt pitch or width.

Factor	T-Profile (Standard)	AT-Profile (Modified)
Tooth shape	Standard trapezoidal (narrow base)	Modified trapezoidal (wider base, optimized root)
Load capacity	Standard	Significantly higher (same pitch and width)
Tooth root stress	Concentrated at corners	Distributed more evenly
Tooth shear resistance	Standard	Improved
Pulleys	T-profile pulleys	AT-profile pulleys (wider grooves)
Interchangeable?	NO. Different tooth geometry. Different pulleys. Do not mix T and AT.
Pitches	T2.5, T5, T10	AT3, AT5, AT8, AT10, AT15, AT20
Material	Polyurethane or neoprene	Polyurethane only
When to choose	Replacing existing T-profile equipment	New designs needing higher load. Heavy linear motion. Upgrades.

T and AT pulleys are NOT interchangeable, even at the same pitch. AT5 pulleys have wider grooves than T5 pulleys. AT10 pulleys have wider grooves than T10 pulleys. Using an AT belt on a T pulley (or vice versa) causes poor engagement, accelerated wear, and potential belt failure. Always verify whether your equipment uses T or AT pulleys before ordering. When in doubt, send us a photo of the belt teeth and pulley grooves. See the Tooth Profiles Explained guide.

AT-Profile vs. HTD: Two Approaches to Higher Load

Both the AT-profile and HTD (High Torque Drive) systems were developed to exceed the load capacity of earlier trapezoidal designs, but they use fundamentally different approaches.

Factor	AT-Profile	HTD (3M, 5M, 8M, 14M)
Tooth form	Modified trapezoidal (wider base, still angled sides)	Curvilinear (rounded, semi-circular)
Design approach	Optimized the trapezoidal form for better stress distribution	Replaced the trapezoidal form entirely with curves
Origin	European (evolution of T-profile)	North American/global (RMA/ISO)
Material	Polyurethane only (steel/Kevlar cord)	Neoprene (standard) and polyurethane
Open-end availability	Standard in all pitches	Available but less common
Linear motion standard	Yes, AT is the European linear motion standard	Less common for linear motion
Comparable pitches	AT5 vs 5M, AT8 vs 8M, AT10 vs T10/8M, AT15 vs 14M	5M vs AT5, 8M vs AT8, 14M vs AT15
When to choose	European equipment. Linear motion. Urethane required.	Global standard. General heavy-duty rotary drives.

AT and HTD are completely separate systems. AT5 and 5M both have 5mm pitch. AT8 and 8M both have 8mm pitch. But AT uses modified trapezoidal teeth and HTD uses curvilinear teeth. They require different pulleys and are never interchangeable. The choice between AT and HTD depends on the pulley system installed on your equipment and whether the design follows European or global standards.

AT-Profile Part Number Format

AT-profile part numbers follow the same metric convention as T-profile: pitch length in millimeters, profile code, hyphen, width in millimeters.

Example	Profile	Pitch Length	Width	Teeth
210AT3-10	AT3	210mm	10mm	70
500AT5-25	AT5	500mm	25mm	100
720AT8-32	AT8	720mm	32mm	90
1000AT10-50	AT10	1000mm	50mm	100
1350AT15-75	AT15	1350mm	75mm	90
2200AT20-100	AT20	2200mm	100mm	110

Divide the pitch length by the pitch to calculate teeth: 1000 / 10 = 100 teeth. Some manufacturers reverse the format. Open-end AT-profile belts are designated by profile and width only (for example, AT10-50 open-end). Texas Belting can cross-reference AT-profile part numbers from any manufacturer. Call 888-203-2358 or see our Pitch Chart.

AT-Profile Materials and Construction

AT-profile belts are manufactured exclusively from polyurethane. The AT system was designed around polyurethane construction, and neoprene AT-profile belts are not produced.

Steel Cord (Standard)

Steel wire tensile cord provides near-zero elongation (0.02%) and is the standard for linear motion, precision positioning, and indexing applications. Steel cord AT-profile belts are the most commonly ordered format.

Kevlar Cord

Kevlar (aramid) cord provides superior flex life around smaller pulleys with low elongation (0.3 to 0.5%). Specified for rotary drives where belt flex fatigue is a concern. Less common than steel cord for AT-profile applications.

Open-End Roll Stock

Open-end AT-profile belts are the standard format for linear motion. Available in all six pitches, sold by the meter, and cut to any required length. Joined with mechanical connectors or heat welding. Texas Belting can supply pre-cut, pre-welded loops from open-end stock.

FDA Compliance

AT-profile belts are available in FDA-compliant polyurethane grades meeting FDA 21 CFR 177.2600 and EU 10/2011 for food contact. Commonly specified at AT5 and AT10 pitches for European food processing equipment. See Food Grade Timing Belts.

Common AT-Profile Applications

Application	Recommended Pitch	Notes
Precision servo drives (compact)	AT3, AT5	Higher load than 3M or T5 at same pitch
Linear motion and positioning	AT5 (light), AT10 (heavy)	Open-end steel cord standard. Near-zero stretch.
CNC routers and cutting tables	AT10, AT15	Heavy gantry, long travel, precision positioning
Waterjet and plasma tables	AT10, AT15, AT20	Extreme gantry weight, high acceleration
European industrial automation	AT5, AT8, AT10	Standard AT-profile on European positioning systems
Packaging machinery	AT5, AT8	Precise indexing at moderate to heavy loads
Food processing	AT5, AT10	FDA urethane for European food equipment
Pick-and-place and palletizing	AT8, AT10	Heavy carriage, fast cycles, precision placement
Medical and semiconductor	AT3, AT5	Low particulate, cleanroom compatible, precision
Bridge cranes and heavy material handling	AT15, AT20	Extreme-load positioning, specialty applications

For a full comparison of AT-profile against other timing belt systems, see the Timing Belt Selection Guide and Tooth Profiles Explained.

AT-Profile Timing Belt Brands We Carry

Brand	AT-Profile Products	Notes
Gates	PowerGrip AT (limited range)	Smaller AT selection. Stronger in HTD and Poly Chain.
Continental / ContiTech	Synchroflex AT3 through AT20	Industry leader in AT-profile urethane. Broadest AT range.
Bando	Bando AT-profile	High-quality Japanese manufacturing
Diesel Belting	Diesel AT-profile	Cost-effective replacement option for common AT sizes
Megadyne	Megalinear AT3 through AT20	Open-end specialist. Strong AT range across all pitches.

Continental and Megadyne carry the broadest AT-profile selections. Call 888-203-2358 with your AT-profile requirements for availability and pricing.

AT-Profile Timing Belt FAQs

What is an AT-profile timing belt?

An AT-profile timing belt is a modified metric trapezoidal synchronous belt with an optimized wider tooth base for higher load capacity than standard T-profile belts. "AT" stands for Advanced Trapezoidal. The family includes six pitches: AT3 (3mm), AT5 (5mm), AT8 (8mm), AT10 (10mm), AT15 (15mm), and AT20 (20mm). AT-profile belts are manufactured exclusively from polyurethane with steel or Kevlar cord.

Can I use AT-profile belts on T-profile pulleys?

No. AT-profile and T-profile pulleys have different tooth groove geometries, even at the same pitch. AT grooves are wider at the base. Using an AT belt on a T pulley (or vice versa) causes poor engagement, accelerated wear, and potential failure. Always match the belt profile to the pulley profile exactly.

What is the difference between AT-profile and HTD?

AT-profile uses a modified trapezoidal tooth (angled sides, wider base). HTD uses a curvilinear tooth (rounded). Both provide higher load than standard trapezoidal, but through different tooth designs. AT is the European standard for linear motion; HTD is the global standard for rotary drives. They use different pulleys and are never interchangeable, even at the same pitch (for example, AT5 vs 5M, AT8 vs 8M).

Which AT pitch is most popular?

AT10 is the most widely specified AT pitch for heavy applications, particularly heavy linear motion gantry systems. AT5 is the most popular for lighter precision automation. Together, AT5 and AT10 account for the majority of AT-profile orders.

Are AT-profile belts available in open-end form?

Yes. Open-end AT-profile belts are available in all six pitches (AT3 through AT20) in polyurethane with steel or Kevlar cord. Open-end AT belts are the industry standard for European-designed linear motion systems. Sold by the meter and cut to any length.

Are AT-profile belts available in neoprene?

No. AT-profile belts are manufactured exclusively from polyurethane. The AT system was designed around polyurethane construction. If you need a neoprene belt at a similar pitch, consider T-profile (T5, T10 available in neoprene) or HTD (5M, 8M, 14M available in neoprene). Note that switching from AT to T or HTD requires changing pulleys.

Are AT-profile belts food-grade?

AT-profile belts are available in FDA-compliant polyurethane grades meeting FDA 21 CFR 177.2600 and EU 10/2011 for food contact. Most commonly specified at AT5 and AT10 pitches. See Food Grade Timing Belts.

Does Texas Belting stock all AT pitches?

Texas Belting stocks AT-profile timing belts across all six pitches. AT3, AT5, AT8, and AT10 are the most commonly stocked with same-day shipping on popular sizes. AT15 and AT20 are specialty pitches with longer lead times on some sizes. Call 888-203-2358 to confirm availability for your specific pitch, width, and length.

Need AT-Profile Timing Belts?

Tell us the pitch, part number, or application details. We stock all six AT pitches for fast shipping from Houston.

Request a Quote

888-203-2358