... certification 3. 10 years in this field 4. reliable quality and reasonable price CRANE CONTROL PUSHBUTTON, Position Spring Return Selector Switch. AC. 50 ... used in wharf, machine tools, textile machineries, etc. Other specifications: 10 lines, 8 lines, 6 lines, 4lines, 2 linesWork environ ment ... frequency is 2-80HZ, the acceleration is 0.79; remote control switch