Polyflex® JB® Belts

Joined belt construction provides increased belt stability, preventing belts from turning over or from coming off drive.

Unique 60° angle polyurethane construction transmits greater loads at higher speeds in less space than conventional V-belts.

Use in place of Polyflex® singles on drives requiring joined sets. A partial listing of applications includes machine tools, computer peripherals, medical equipment, library equipment, small appliances, blower drives and dough mixers.


  • High Modulus Polyurethane compound resists fatigue, wear, ozone, and most environmental conditions.

  • Precise casting method eliminates layers and overlaps for smooth running and low vibration.

  • Ribbed backing provides greater lateral stability and relieves bending stress.

  • Working temperature range: -54°C to +85°C.

  • Joined belt construction provides high stability, preventing belts from turning over or coming off of the drive.


Polyflex® JB® Belts are available in 3M, 5M, 7M, and 11M cross sections.

The Polyflex® JB® belt part number is comprised of the number of belt strands, cross section, effective length and the “JB” signifying joined band construction. For example; part number 3/5M1000JB represents 3 strands joined together, 5mm top width for each belt strand, effective length of 1000mm and joined band (JB) construction.

Manufacturing lead times and minimum order quantities may apply to matched sets and to rib configurations other than those listed. Minimum order quantities do not apply for belt lengths listed. Contact Customer Service for details.

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