This 30mm guide bush is a popular router accessory that fixes to the router base and acts as a small ring fence The Trend GB30 is a 30mm guide bush designed to guide the router when using a template. It fits directly to the Trend T3, T4, T5, T5 MK2, T9, T10 and T11 and some other light duty routers. Features: This guide bush guides the router when using a template Fits directly to Trend T3, T4, T5, T5 MK2, T9, T10 and T11, and some other light duty routers Will fit other makes when used with GB/5, GB/PLATE or UNIBASE Sub-base Specification: Diameter: 30mm