For use on crank-open windows and vents in recreational vehicles These cranks are superior to plastic cranks that can become brittle over time, or whose grooves can be stripped out Long 1 inch stems extend the reach of these cranks for RV windows and vents Diecast constructed cranks with zinc-plated finish Internally serrated cranks for 5/16 inch spline size Easy to install with a Phillips head screwdriver Includes installation fasteners Please refer to the line art drawing for dimensions and compare with your needs before ordering