DangShan YYT28 hydraulic rock drill is a new  generation drilling equipments
Of our factory, which takes more than 18 year careful development. And obtained the "National Key New Product"
And "Technical departmentinnovation Fund".
A number of patented technology makes this product has many outstanding features: Small original driving force, fast speed, stability control, low noise, simple, reliable, easy maintenance, flexible and mobile etc.
The YYT28 is made for general excavations, quarrying and bolting with hexagonal shank rods with a shank size of 108mm(41/2")*22mm(7/8"). The YYT28 can use water  flushing or air flushing.
YYT28 is a hydraulic rock drill to drill diameter 32mm(1?") to 50mm(2") holes.
http://www.dsrockdrill.com