Insulated Muti-Purpose Coupler Height Gauge Includes the #148 Whisker® Coupler & #158 Scale Whisker® Coupler. - Kit. EASY TO ASSEMBLE & USE Includes the #148 "Whisker®" Coupler & #158 "Scale" "Whisker®" Coupler. A must have tool for gauging mounting height, correct coupler height, trip pin, and permanent uncoupler heights for achieving trouble free coupler performance. Also has a built in HO track gauge. "Takes the guess work out"