DH99 Drills are a series of 4 inch (102mm) bore drifter drills for general mining, tunneling, and construction work The DH99 drill can be mounted on Screw Feed Aluminum Guide Shells for drifter or long-hole drilling
The main design construction features many options:
Backheads for remote control automated drilling
Threaded exhaust ports for noise control equipment
Chuck end parts for 1 1/4″ round tangential shanks