... P.A.(including caterpillar assembly,driving roller, guiding roller,track roller,carrier roller,etc.). 4,Power head—main body ... Construction Elevators(multi-speed, stepless-speed), Concrete Mixers (rotary-drum-type, double-horizontal-shaft), Concrete Batchers, ... oil-burning, gas-burning, coal-burning), Stabilized SoilMixing Plants, Rotary Drilling Rigs... ( function(){ var aBigImageSrc = [ 'http:// ...