The plastic sheave degrades and breaks on older Hobie® 16 downhaul cheek blocks and the entire block must be replaced. Also fits Sol Cat 18. Hole spacing 1/2" on center from side to side; 2-3/4" on center from end to end.
To install, use four #19-5031 6-4 rivets and four #19-5020 sealing casings. Compare to Hobie Cat® #20710000.