Park Tool TW 5 Ratcheting Torque Wrench. With today's lightweight components, torque wrench use is no longer an option it's a must for every mechanic. The Park Tool TW 5 is a high quality, ratcheting, click type torque wrench that accurately measures and applies the proper amount of torque to a component's threaded fasteners. It is designed for lower torque settings used for proper seat post, seat clamp and handlebarstem applications. Includes its own protective case for safe keeping in the shop or while traveling.