Main Features a. ST series drilling rig adopts CG140 model auto transmission, has 10 rotation speeds and easonable speed range, with eight forward roation gears and two reverse rotation gears, high speed, strong stroke and wide scope of application. b. Large engine power and two reverse rotation gears, can easily solve the drilling work accident. c. The operation handles are fixed together in reasonable layout to make it more convenient for workers to operate the machine. d. Equipped with normally closed hydraulic chuck, operation is flexible and reliable e. Spindle and hoist can be operated separately. f. Spindle has big inner diameter, able to use big hexagonal drilling rod.