A Set of three 1937-1962 Chevy 216,235,261 Custom intake manifold alignment adapter rings. Precision machined from 303 stainless steel. Will never rust. These rings will allow you to install a "large port" 235/261 intake manifold on an earlier "small port" 216 motor. Will also allow you to install an earlier 216 "small port" intake manifold on a later 235/261 "large port" motor. Most of the original era correct multi-carb. speed equipment intake manifolds from the 1950's were produced for small port 216 motors. These rings work great in properly aligning & sealing these older original intakes to the later 235/261 motors. Most of the new modern reproduction multi-carb. speed equipment intakes are produced with the large 235/261 ports. These rings work great in properly aligning & sealing the modern intakes to the earlier 216 motors. These rings are NOT correct if you are bolting a 235/261 intake to a 235/261 motor... Or you are bolting a 216 intake to a 216 motor. Set of 3 rings.... $35 W/FREE U.S. shipping PM us for more info.