1) High quality aluminum alloy die cast gearbox 2) High accuracy worm gear and worm shaft 3) Less noise and lower temperature Model size:025,030,040,050,063,075,090,110,130,150speed ratio:5,7.5,10,15,20,25,30,40,50,60,80,100Main materails:High quality aluminum housing from 025-090,high quality iron cast from 110-150high quality Tin bronze worm wheelhigh quality NSK bearinshigh quality synthetic ...