Specifies the external diameter and positioning of the front face of the collar with respect to the 7/24 taper in the case of attachment by the front face.

BS 1660-8:1988
Original price was: $264.16.$132.00Current price is: $132.00.
Machine tapers-Specification for collar dimensions for 7/24 taper tool shanks and equipment
BSI Group , 09/30/1988

