This is a 12 gauge, CNC laser-cut stainless steel block-off plate for the 13B, Series 4/5 (1986-1991) NA (non-turbo) Air Control Valve (ACV)w/ laser etched Pineapple Racing logo located on the lower intake manifold. Use a stock ACV gasket and/or silicone gasket material underneath for a positive seal. As with any product that defeats an emissions device, it is intended for off road use only!