Mounting adaptor for Radial JDI, flanged for easy mounting. Made from 14 gauge steel, the J-clamp is made tough to handle the abuse of professional touring. The top is screened with user-writable tabs that are designed for wax pencil or can be more permanently designated with an indelible marker. Installing it is easy! One simply unscrews the book-end outer shell from the desired Radial interface and slides the J-clamp over in place. The same 4 screws are used to secure the unit. The J-clamp features extended wings that are pre-drilled to allow quick installation on any flat surface.