Boat part number 1113484 is a new 1 1/8" wye "Y" tee fitting from TH Marine, part number Y-118-DP . Commonly used on Excel Boats, part number BC-221 , but may be used on other boats.
A fitting with three openings, a wye is used to create branch lines. It is a type of tee fitting which has the side inlet pipe entering at a 45° angle, or an angle other than 90 degrees. A standard wye is a "Y" shaped fitting which allows one pipe to be joined to another at a 45 degree angle. Wyes are similar to tees except that the branch line is angled to reduce friction and turbulence that could hamper the flow. In boat applications, a Y fitting can be advantageous because it can allow better drainage and may be easier to install due to space limitations.
This Y fitting is constructed out of black plastic and measures approximately 3 3/8" W x 3 7/8" H x 1 1/8" D overall. It has (3) 1 1/8" Dia. barbed hose connections. See photos for measurements.
Specifications: