Check Valve Kit
OEM: Mercury
Replaces: Mercury 17997A1
For 1988-98/2002-09 Alpha Gen II, Bravo, Bravo X, Bravo XR, Bravo XZ, Blackhawk & Vazer transom upper drive housing.
also crosses with:
Sierra: 18-2715
GLM: 12930
Mallory: 9-78005
UPC: 840080481913