Trench DaggerM. R. Mayhem
is on back order
These are my take on the British World War I Robbins of Dudley push dagger.
They are 3/16 inch thick 80CRV2 with a 4 1/2 blade (4 inch cutting edge on the longer edge) and 1/4 inch thick handles.
They come with a black kydex sheath with strap for retention, which is somewhat similar to the leather sheath the original came with.