28mm diameter low noise planetary gearbox CE,RoHS compliant 13,17.5,21. ... 4 to 1/1975 28mm diameter low noise gearbox Model No.: ZYM-P28 gearboxOther reduction ratio of ... 28mm gearbox: gearbox length(mm)stadgereduction ratio 34.1 3.4 ... 18,19,20,23,26,28,35,4551.3 40,45,50,56,65,74,85,95,102, ... 1304,1556,1975 28mm Low noise Planetary gearbox 13~26Kgf-cm CE RoHS