Motion Pro is dedicated to producing the most versatile, unique and durable products for professional and home use. Motion Pro tools are designed to be simple to use, yet durable enough to withstand the harshest conditions. One of their goals is to offer tools of convenience. Do it right the first time with Motion Pro Tools. Four-piece set includes three common sizes for use on most modern street bikes. Includes 4.0, 4.5 and 5.0 mm sizes along with one additional 5.0 mm size specially designed for the Suzuki Hayabusa and other Suzuki models that use the same seal. Properly aligns valve stem seal to valve guide so seal snaps on straight every time. Provides for quick and easy installation of valve stem seals on multi-valve cylinders. Contoured design in bottom of handle cradles and protects the delicate inner lip of the valve stem seal while directing tool force to the sturdy outer rim.