Dormer B3344 0052242 expanding hand reamer with 5 flutes, No. 4 internal designation, and HSS construction. Designed for precision hand reaming operations, this reamer provides accurate hole sizing and finishing in a range of materials. The expanding design allows for adjustable cutting diameter to accommodate wear and achieve tight tolerances.

Adjustable hand reamer with replaceable blades (B335) and a square drive, diameter range 12.0 - 13.5mm number 4 with an overall length of 135mm and long replaceable blades with 9mm taper lead, according to DORMER standard for light duty sizing of uninterrupted holes, HSS with bright finish for machining free machining, plain carbon and alloy steel, grey and malleable cast-iron, wrought and cast aluminium and copper or copper alloys.