These slotting saws are shaped to fit into the bridge pin holes, cut the slot and define the string " ramp" at the front of each hole.
This set provides two gauges; the smaller (.028"/0.7mm) is for unwound strings. The wider one is 0.051" (1.3mm).
The cutting edge is 45mm long. Overall length 180mm. Nicely rounded hardwood handles. Made of chrome alloy steel.