This spiral flush trim Bit is mainly used for acrylic, wood and MDF up to a 1/2" Thickness. Double ball bearing pressed., #46297, direction down-cut, diameter (D) 1/4, cutting height (B) 1, shank (D) 1/4, overall length (L)\ 3, type down-cut, replacement, bearing 47723 (2), screw #67134, 46297 Solid Carbide ultratrim spiral trim 1/4 dia x 1 inch x 1/4 shank with double ball bearing down-cut