1.High quality Aluminum housing 2.long life service 3.large speed ratio range 4.high efficiency and save energy Rv series worm gearboxesMode size:025,030,040,050,063,075,090,110,130,150Speed ratio:5,7.5,10,15,20,25,30,40,50,60,80,100High quality aluminum housing from 025-090model sizehigh quality iron cast housing from 110-150NSK,FKG,C&U bearingsTin Bronze worm wheelhigh quality synthetic ...