These hollow mortise chisel and HSS bit combinations are offered as replacement sets for mortisers and drill-press mortising attachments. Though inexpensive, they are well made and hardened to Rc48-52. Shank sizes are 3/16" to 3/8" in diameter on the bits and 5/8" in diameter on the chisels. Please double-check your mortiser's capacity before ordering.
For easy chisel sharpening, a pair of diamond hones is recommended, one for the basic grind and the other to put a micro-bevel on chisel corners. The corners need the higher bevel angle for strength. These are available separately.