1.special for SPT test, get ISO9001-2000 2.good detachability, easy to operate. 3.hydraulic feed. 1. APPLICATIONS: Geological drilling for railroad, highway, bridge tunnel, foundations of power station, Civil and industrial buildings, also drilling anchoring hole and blasting hole etc.2. FEATURESSpindle type mechanical transmission, hydraulic feed.Hydraulic retracting lets drill body away from ...