The TracTuff water bypass is by far the highest quality coolant delete option there is for your RBC setup on a RAA, RBB, RBC, and RSP style cylinder head. Precision machined in the USA out of billet 6061-T6 aluminum, this water bypass will help you bypass the coolant portion on your RBC manifold leak free.

The O ring grooves machined into the bypass adapter creates a waterproof seal way better than Hondabond will provide on other competing water bypasses.

With this water bypass, you can expect your RBC manifold to go from too hot to touch, down to just mildly warm. This will help keep the intake air cool as it flows through the intake manifold, and into the engine.

From Tractuff: "

The OG water bypass adapter. Imitated but not duplicated and still the best looking, best fitting (leak free!), and now the least expensive!

The water bypass adapter allows K24A_ and K20Z3 (RAA, RBB, RBC, and RSP style cylinder head) owners to run the more popular aftermarket intake manifold options that were designed for the earlier PRB/ PRC k series cylinder head flange. PRB/ PRC style manifolds do not cover the right most portion of the intake manifolds flange, so the coolant bypass and EGR passages are left exposed. The water bypass adapter allows you to make the water passage connection as well as cover the unused EGR passage.

Even if you don't plan on running a PRB/ PRC style manifold... there are plenty of benefits that make this product a smart purchase! Benefits such as a reduction in intake manifold temps by eliminating the heat transfer associated with hot coolant running through the manifold or my personal favorite, NO LONGER HAVING TO DRAIN COOLANT when removing the intake manifold for maintenance or swaps!"