Depth 3-1/4" Width 5-1/4" max Height 5-13/16" .Clearances (W) 3" max (H) 4-5/16"
This design was used for tunnels that had problems with falling rocks. It can be made with or without the front braces, and adds a superb touch to any layout. All materials are strip basswood and include Nut/Bolt/Washer castings. Full-size templates are enclosed for various clearances: 16' wide for standard NMRA Specs and 14' for Narrow Gauge layouts. The ‘S’ scale model’s clearance is excellent for On30.