Not go gauge for caps E26, E26/50x39, E26/51x39 & E26d, 7006-29L-4

Not go gauge for caps E26, E26/50x39, E26/51x39 & E26d, 7006-29L-4 

Purpose: 

To check the minimum outside (major) diameter of the screw thread, dimension d, of E26, E26/50x39, E26/51x39 or E26d caps on finished lamps. 

Testing: 

When the gauge is placed over the thread of the cap on a finished lamp, held cap uppermost, the central contact shall not project beyond surface X. Only the weight of the gauge itself shall be used in the test.