Plough gauges are a European origin tool used to cut straps. They are used in a pushing motion. The blade is in line with the handle and will cut wider straps more easily than a draw gauge. These come from fine European makers like Dixon, Blanchard, Vergez-Blanchard, and Mayer-Flamery.
Dixon and other British Makers
Draw gauges are used to cut leather strips. The draw gauges are from American makers such as CS Osborne, HF Osborne, and once in a while draw gauges from Henry Sauerbier and others. They have all of the gibs/shims and all come with a new re-profiled and sharpened blade.
These are designed to put on your finger and pull away to cut laces and strings. They'll adjust up to about a a half inch. I have stripped these down, primed and painted, then sharpened the blades. These all have good blades, unlike a lot of them you find.