Held in place by the Bench Clamp (LB0858-001) or by a retort stand and boss head. This 50mm diameter nylon pulley is fixed to the end of an 20mm long x 8mm diameter anodised rod.
The rod supporting the pulley is straight in one plane, but edgeways the rod is offset so that the pulley groove is in line with the rod. 
Genuine IEC product.
Instruction sheet included.