Incl. 18mm & 24mm outside diameter aluminum adapters. Billet 6061-T6 aluminum frame provides unmatched strength and stiffness and lower weight. Quick release system presses straight against the retainer to eliminate side loading the valve and keepers. Works on all motorcycle, ATV, UTV, and small engine cylinder heads. Fully adjustable top and bottom. Aluminum lower adjuster will not damage or scratch valves. Includes two universal fork style tips/adapters. Durable blue anodized finish with laser engraved markings. Simple, fast, and easy to use.