These stainless steel bulkhead fittings are ideal for use in custom applications where the AN plumbing must pass the frame on tubing on a street rod or race car. These fittings eliminate the need for tabs or brackets on the frame and allow the plumbing to be hidden on the inner edge of the frame rails. Fits through tubing from 1.5" to 2.0" thick. Sold individually w/ matching Flanged bulkhead nut.