Description
120LT312-6A4 Timing Pulley, 12 Teeth, LT Pitch, 5/16 in Bore
The 120LT312-6A4 is a 12-tooth LT (0.0816 in trapezoidal) timing pulley with a 5/16 in finished bore, machined from aluminum with a clear anodized finish, built for 0.3125 in wide belts. Machined from solid stock, never sintered or powdered metal.
Specifications

Dimension key for this construction type. Values for this part number are in the table below.
| Specification | Value |
|---|---|
| Part Number | 120LT312-6A4 |
| Teeth | 12 |
| Pitch | LT (0.0816 in trapezoidal) |
| For Belt Width | 0.3125 in |
| Pitch Diameter | 3.1169 in |
| Outside Diameter | 3.0969 in |
| Bore | 5/16 in finished bore |
| Face Width | 0.875 in |
| Overall Length | 1.5 in |
| Hub Diameter | 1.5 in |
| Construction | Standard Hub |
| Set Screws | 2 x 8-32 |
| Material | Aluminum (no sintered or powdered metal) |
| Finish | Clear Anodized |
| Weight | 0.41 lb |
| Country of Origin | United States. ISO 9001:2015 certified manufacturing. |
Applications
- Instrumentation, office equipment, and precision positioning drives
- 3D printers and desktop CNC equipment
- Robotics, medical devices, and packaging machinery
Belt Compatibility
The 120LT312-6A4 runs LT (0.0816 in trapezoidal) belts in 0.3125 in width. The pitch is standardized, so belt and pulley brands can be mixed.
Cross Reference
The 120LT312-6A4 interchanges with these equivalent part numbers, per published manufacturer interchange data:
| Manufacturer | Equivalent Part Number |
|---|---|
| Mitsuboshi | 120LT312-6A4 |
| Stock Drive Products (SDP/SI) | A 6A 61-20NF03110 |
| Neuman | 120LT-312 X 1/4 6 |
| York | 120M312-2A X 5/16 |
| Powerdrive | 120LT312-6A4 |
Always verify dimensions and bore size before substituting part numbers across manufacturers.
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Multi-unit and OEM quantities qualify for volume discounts. Call or email for a quantity quote.
Frequently Asked Questions
What belts fit the 120LT312-6A4 pulley?
LT (0.0816 in trapezoidal) timing belts in 0.3125 in width from any manufacturer. The pitch is standardized, so belt and pulley brands can be mixed.
Does the 120LT312-6A4 replace the Mitsuboshi 120LT312-6A4?
Yes. Published interchange data crosses the 120LT312-6A4 directly to the Mitsuboshi 120LT312-6A4, as well as Stock Drive Products A 6A 61-20NF03110, Neuman 120LT-312 X 1/4 6, York 120M312-2A X 5/16. Verify dimensions and bore before ordering.
Does the 120LT312-6A4 ship from Houston?
Yes. Stock items ship same day from our Houston, Texas warehouse. Call (888) 203-2358 to confirm availability.
Need a quote on 120LT312-6A4?
Houston warehouse, same-day shipping on stock items.
Call (888) 203-2358All third-party part numbers and trademarks referenced are the property of their respective owners. References are for compatibility identification only and do not imply affiliation or endorsement.
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