Timing belts are a fantastic way of transferring the rotational movement (of a stepper motor) into a linear movement (along a rail) and these belts T5 are excellent for these tasks. They have a special profile with rounded teeth reduces slippage. They are often used for 3D printers and CNC machines.
This strap is 600mm long (apart teeth 120 2.5 mm) and is 10mm wide. It is a closed belt.