Nylon fiber OS adapters are designed for use in frames with worn-out, oversized bottom bracket shells Replaces standard nylon fiber overmolds found on Origin8 Revolvr BB30 and PF30 outboard thread-together bottom brackets* * Use BB30 OS adapters with Origin8 Revolvr BB30 outboard thread-together bottom brackets 211051 and 211052 * Use PF30 OS adapters with Origin8 Revolvr PF30 outboard thread-together bottom brackets 211053 and 211054 Requires a special installation/removal tool (J&B# 610817) 68/73mm x 46~46.1mm PF30 Nylon Fiber Black