For 1967-98 Mercury/Mariner 4-cyl, 65-85 Hp | 6-cyl, 90-150 Hp | V6, 135-200 Hp outboards.
ID: 3.5″ | OD: 3.875″ | W: 0.1875″

also crosses with:
Sierra: 18-7157
GLM: 83415
Mallory: 9-76542