GearWrench 2488D 4-1/8” Engine Cylinder Flex Hone GearWrench 2488D 4-1/8” Engine Cylinder Flex Hone requires no setup, is designed to be used with a variable-speed 3/8” electric hand drill and move the Flex-Hone up and down in the cylinder until desired are obtained.

GearWrench 2488D 4-1/8” Engine Cylinder Flex Hone can hone engine cylinders 3-1/4” to 4-1/8” and 83mm to 105mm in diameter to produce a plateaued finish for fast ring seating and better oil retention for longer engine life.