Abstract: A device for retaining a set of slip-type pliers in functional adjustment is disclosed. The device comprises a shouldered dowel pin axially slidable between two positions, the first permitting freedom of adjustment between the two plier members, the second position retaining the plier members in functional adjustment while permitting freedom of use thereof. The dowel pin is retained in its second position by a spring mounted therewith and carried by one of the plier members. An alternative embodiment incorporates a modified pin pivotally connecting the two plier members in rotating relation with each other. This pin is spring mounted and includes a shoulder or cap which selectively engages each of a series of spaced counterbores within the adjusting slot of one of the plier members for retaining the plier members in functional adjustment with each other during use.