These OEM housings are available in 2.7", 3.0" AND 3.625" OD to match your drill and drilling conditions. These versatile housings are manufactured from 4145HT, utilize the Vermeer® OEM bit bolt patterns (see table below) and accept 2-cell DCI, Spot-D-Tek® and Radiodetection transmitters. StraightLine's unique 3-piece design; housing, nose piece and tail piece will deliver longer service life than the OEM and other aftermarket housings.