Features and Benefits: OTC s Large Valve Spring Compressor is designed to quickly and easily compress valve springs on overhead valve engines Includes two valve spring adapters which fit valve spring retainers up to 1 inch (25 mm) and 1-3/16 inches (30 mm) Unique direct action compressor lever gives better visibility of valve spring retainers located in difficult access areas Jaw opening of 1-3/8 inches to 5-5/8 inches (35 mm to 142 mm); throat clearance of 5-7/8 inches (150 mm) Durable plated finish; high-grade materials ensure quality performance over the lifetime of the tools