Freud 3-1/2" (Dia.) Raised Panel Bit w/Backcutters with 1/2" Shank (99-566) Shims are included to allow adjustment of tongue thickness from 7/32" to 1/4" for maximum versatility and compatibility. Patented design allows these bits to produce a full 1-1/2" wide reveal for traditional raised panel doors. Included 54-562 radius backcutter gives double-sided appearance and can be replaced with optional 54-560 square backcutter for a more contemporary look. Cuts all composition materials, plywoods, hardwoods, and softwoods. Shims are included to allow adjustment of tongue thickness from 7/32" to 1/4" for maximum versatility and compatibility Patented design allows these bits to produce a full 1-1/2" wide reveal for traditional raised panel doors Included 54-562 radius backcutter gives double-sided appearance and can be replaced with optional 54-560 square backcutter for a more contemporary look Cuts all composition materials, plywoods, hardwoods, and softwoods Use on table-mounted portable routers