Use for starting a 1-1/4 in. hole drill to a depth of approximately 1/4 in., stop hammer, remove guide plate and center pin. Place core bit back into the grooved area and resume drilling to required depth of hole. Adds bit stability and reduces bit walk.
- 1-1/4 in. Dia
- Used with core bit 48-20-5015
- For bit stability - reduces bit walk