Moroso 68791 Moroso Filtered Valve Cover Breather - Clamp-On - 1in IDMoroso 68791 Moroso Filtered Valve Cover Breather Clamp On 1in ID Clamp On Breather, 1" I. D. Clamps onto a 1" outside diameter tube, clamp included Fits Moroso Billet Alum. Vacuum Relief Valves Nos. 22633, 22636 and 22637 Provides maximum protection against dirt and airborne debris without restricting air flow Cleanable and re usable: oil before use Not legal for sale or use on pollution controlled vehicles