Rub collar for 3/4" arbor only, #962, (D) Diameter 2-3/4, (d) Bore 1/2 & 3/4, (a°) Angle 45º, (B) Cutting Height 2-1/4, (R) Radius 1/2, B1 2R1 3/16, Optional Rub Collar C-027, 962 Carbide Tipped 3-Wing Crown Molding 3/16 Radius x 45 Degree x 2-3/4 Dia x 2-1/4 x 1/2 & 3/4 Bore.