Klein Tools 32596 HVAC Slide Drive™ Multi-Bit Screwdriver / Nut Driver, 8-in-1This 8-in-1 HVAC Slide Drive™ Screwdriver / Nut Driver has a unique, patented head that slides back and forth to switch from 1/4-Inch to 5/16-Inch magnetic hex-head screwdriver. Convenient thumb nut locks tip setting. It includes a specialty bit for the installation/removal of common TR-4 Schrader® valves as well as regular 1/4-Inch and 3/8-Inch nut drivers plus Phillips/slotted double-ended bits. Offers the HVAC tech the convenience of having magnetic nut drivers on a multi-bit screwdriver.8-in-1 Screwdriver / Nut Driver with unique, patented head that slides back and forth to switch from 1/4-Inch to 5/16-Inch magnetic hex-head screwdriverThumb nut locks tip settingFeatures a specialty bit for installation/removal of common TR-4 Schrader® valvesIncludes 1/4-Inch and 3/8-Inch hollow nut drivers, as well as #2 Phillips, 1/8-Inch (3 mm) and 1/4-Inch (6 mm) slotted screwdriver tipsCushion-Grip handle for greater torque and comfortGreat for HVAC applications including thermostat installation and control workU.S. patent 7,654,175 B2