Detail ofSteel Wheel is as follow, TO41S+SUSPENDPULLEY CODE ROLLERDIA A ROLLER WIDTH HEIGHT B CENTER C SCREW D CENTER E THREAD F STEEL STAINLESS TO41S-19 TO42SS-19 Ø19mm 18 72.5 64.0 40 30 M8 TO41S-20 TO42SS-20 Ø20mm 19 74.0 64.0 40 30 M8 TO41S-22 TO42SS-22 Ø22mm 19 75.0 64.0 40 30 M8 TO41S-24 TO42SS-24 Ø24mm 20 76.0 64.0 40 30 M8 TO41S-25 TO42SS-25 Ø25mm 21 76.5 64.0 40 30 M8