Distance Measuring Wheel

12" mechanical type distance measuring wheel,it has inch and MM graduation,but can not use synchronously. Counter Limited Min./Max:5 digits 10cm-9999m 0.3ft-32800ft Package:67*52*30cm 12/7kgs 10pcs/ctn 12'' Measuring Wheel Standard Quality control(Q.C.)&Inspection 12'' counter test Requirements: 1.Set 8 kilometers/per hour for idle running(W/O zeroized). 2.Zeroizing per every 5 meters,totally 5000 times test. 3.Replace new twsiting;pressing leaf spring and auxiliary after pass the above Q.C.test. Any below situation occurred during testing is N.G. 1.Zeroizing incompletely & imprecisely. 2.Gear wheel get stuck or turning W/O moving forwaed while testing. 3.Plastic part broken while testing; Precision gauge for wheel O.D.test 1.Only passing the Max.& Min.tolerance of O.D.(outside diameter) gauge is acceptable. End surface & concentricity test Any below situation occurred during testing is N.G. 1.Single side of end surface:move up and down over 0.5mm 2.Circling motion:move up down over 0.2mm Complete whole product test 1.Correctly put the maesuring wheel into the testing gauge;Set speed at 8 kilometer/hour for running in clockwise way;Zeroizing per every 20 seconds and break one time;Totally 20 times test for clockwise running testing; 2.If above testings are OK,then test again in reversed way; Any below situation occurred during testing is N.G. 1.Zeroizing incompletely;plastic parts broken; 2.wheel assembled should be properly,avoid any too tight or too loose 3.Gear wheel get stuck; Walking test 1.Tolerance:5mm/per 1M by 30 meters walking test Falling test 1.Falling from 1.5M high position in any angle for three times; Any below situation occurred during testing is N.G. 1.Plastic parts broken or disintegrated; 2.Zeroizing function is not working well; Appearance and others 1.Appearance W/O impact;scrape and spot; 2.Twist locking aliminium tube couldn't over 2 cycles; 3.Alimunium tube should be easily telescopic and cannot fall off; ONLY PASS ABOVE TESTE IS ACCEPTABLE,OR BELONG TO "N.G.",SHOULD REPLACE THE DEFECTIVE PARTS AND RE-TEST AGAIN.