Abstract: The disclosed swivel adaptor (20) is assembled into two sections: tool member (40), and adaptor member (60). These two sections are pivotally attached, and can pivot with respect to each other around pivot axis (54). Pivot axis (54) is angled off-axis with respect to the longitudinal axises of the adaptor sections to allow various angled positions for adaptor (20). The angle between the tool port end (42) and adaptor port end (64) being adjustable between an in-line position where members (40) and (60) form a relatively straight adaptor, and a plurality of angled positions where the longitudinal axises of ports (42) and (64) are not parallel. Adaptor (20) has an pivotal air passageway connecting end (45) to end (65). In the straight position, tabs (72) snap into place to provide a holding force to keep the two sections from pivoting during use. By applying a sufficient twisting force on the two sections, tab (72) slips loose and the two sections can rotate about axis (54).