Kadee #811 O-Scale Between-the-Rails Delayed-Action Magnetic Uncoupler

Kadee #811 O-Scale Between-the-Rails Delayed-Action Magnetic Uncoupler     #812 Multi-Purpose Coupler Height Gauge - O Scale A must have tool for gauging correct coupler, trip pin, and permanent uncoupler heights for achieving trouble free coupler performance. "Takes the guess work out"Coupler Height Gauge:1) Provides instant visual reference of proper coupler height2) Gauges car underbody height from the rail3) Gauges track width (N.M.R.A. Standard)4) Gauges wheel width (N.M.R.A. Standard)5) Gauges proper height of trip pin6) #811 Uncoupler Mounting Jig (#812 Only).