For Volvo Penta Sail Drive models 120, B, C, D, E, MS25S , MS25S-A, MS25S-R, S120C
Outside Diameter: 3-13/16″
Hole Distance: 2-7/8″
EMP Aluminum anodes conform to Mil-Spec A-24779(SH)

also crosses with:
Canada Metals CM851983A
GLM 12781
Technoseal 00706AL
Reliance AMD-876286