The digging reamer consists of finger type reaming blades welded to a sleeve type body, which is locked into the bit assembly between the threaded connector and locking bowl, and is friction held when the bit shank is tightened into the threaded connector. A heavy facing of tungsten carbide particles is applied to the cutting and reaming edges.

Water well drillers, using Type AC bit and 2³/8" (60.3mm) OD drill rods on light weight equipment, ordinarily drilling water wells using 2" to 4" (50.8-101.6mm) casing, occasionally use the Type AC digging reamer. When the driller wishes to drill a larger hole for 6" (152.4mm) casing, ordinarily requiring Type SH bit, the driller can use an 8¾" (222.2mm) digging reamer on the regular Type AC assembly with 4¾" to 6" (120.6-152.4mm) blades, which serve as a pilot bit for the digging reamer. Similarly, water well drillers regularly using the Type SH bit can use the Type SH digging reamers as shown in the parts list, in sizes to 26" (660.4mm).