The Big Bullet block is exceptionally free rolling with a large 11/2 ft (38mm) sheave that accommodates up to 3/8 ft (10mm) line. Use exit and in-line exit blocks for tuning lines into and out of masts, booms, and through decks. Use exit blocks with cams on mast for halyard controls. Upright lead blocks are perfect under decks and at mast bases. 3/8 in LINE, MWL 600#, BS 2000# WT. 41/4OZ SHEAVE 11/2 in