Aluminum. Located on the bottom of the external power trim pump assembly.
Fits Mercury/Mariner 30/40 4-Stroke, 40 (4 cylinder), 50 (3 cylinder 1987‑1997), 55 (3 cylinder), 60‑90 (3 cylinder 1987 & newer), 75 (4 cylinder), 75/90 4-Stroke, 100‑125 (4cyl), 115 (6 cylinder 1984‑1988), and all V‑6 and OptiMax outboard engines. Quicksilver Branded, Clamshell Package Point of Sale Packaged.