This water pressure gauge is compatible with marine outboard engines rated at 135HP, 150HP, 175HP, 200HP, 225HP, 250HP, 275HP, 300HP, 350HP, and 400HP.It replaces part numbers 881879T26, 881879A20, 881879A19, and 8M6000639.Constructed from ABS and metal, it is designed for use in both freshwater and saltwater environments.The package includes one water pressure gauge.