| 摘要 |
A jack stand with a safety locking device whereby the pin for locking the extensible member with respect to the base or housing is keyed so as to prevent withdrawal of the pin until rotated into an aligned position. The through hole in the base for receiving the locking pin is slotted so as to receive a pin having projections for fitting through the slots, with the projections on the pin preventing withdrawal when the pin is not in the aligned position. |
