connector collars unhindered therethrough when the string has been lifted or lowered the required distance through sleeve 2 and it is then desired to let the string hang by its own weight suspended in the wellbore the lever 27 is depressed downward moving arm 22 against sleeve 1 thereby pivoting it about pins 30 until teeth 13 are brought into contact with the tubing then the weight is eased down on the tubing forcing abutment shoulder 15 against inner shoulder 17a of bottom plate 17 this junction of one side of the bottom of sleeve 1 with the plate 17 applies a rotational moment to the sleeve forcing it into further pivotal movement toward the string and causing teeth 13 to bite into the wall of the string thereby securely gripping the string and holding it there the perpendicular faces of the teeth are arranged to bite deeper into the tubing string with increasing applicaton of application force and the sloped lower faces of the teeth allow them to be cammed out of engagement with the tubing upon upward movement of the string through the sleeve such an upward movement removes the rotational moment from the sleeve and spring 21 urges the sleeve into the canted non engaging position once again should the sleeve adhere to the string as it moves upward it will be dislodged by abutment with head 28 and return to its non engaged position referring now to fig4 6 alternate constructions of the invention are illustrated which embodiments are particularly advantageous when access to the end of the tubing string is hindered and it is desirable to place the clamping or suspension means of the string from the side rather than over the end in fig4 an alternate housing construction is shown as.