Weld on 3.5" v-band flange for S400 Race covers that have a hose outlet. Flange is same size as standard S400 compressor housing. Has recess in face to fit factory type cast elbows. Mating flanges and clamps available. Once you cut back the hose end of housing this is a slip fit so be careful not to cut too much off. If you do not have access to a welder we can weld it for you, select option to have welded send in your housing and we will include flange and return shipping weld on flange and ship back to you.