Marples Irwin M2154 Mortice & Marking Gauge with Thumbscrew Adjustment MAR2154 Marples 2154 Combination mortice and marking gauge made of sealed rosewood with a brass pull slide to adjust the extra spur for use as a mortice gauge. The knurled brass thumbscrew is used to secure the stock and has Brass facing strips and a thumbscrew adjusting slide. MAR2154