The Internal Combustion Rock Drill Type YN 27C (YN27T) has functions of drillhole, cleavage, bruising, tamping and ... its parts are interchangeable with international homogeneous products. Applications The Internal Combustion Rock Drill Type YN 27C (YN27T) has functions of drillhole, cleavage, bruising, tamping ... volumes)12:1Clearance of spark plug0.50.7 mm YN27C Rock drill