Lezyne ABS Air Bleed System The Lezyne Air Bleed System (ABS) is an in-line air pressure release valve built into Lezyne Flip-Thread Chucks and Flex Hoses. When using an ABS equipped Lezyne floor pump to inflate a Presta valve tube, pressing the ABS button releases the air back pressure. Releasing this back pressure allows for the easy removal of the Flip-Thread Chuck without the risk of unscrewing removable Presta valve cores. When inflating Schrader valve tubes, pressing the ABS button releases air from the tube to adjust tyre pressure. ABS is patent pending worldwide. Replacement ABS Flip Thread Chuck for all High-Pressure Floor Drive floor pumps and all Micro Floor Drive hand pumps. Specification Replacement flip chuck (Road (HP)). The Air Bleed System (ABS) is an in-line air pressure release valve built into Lezyne Flip-Thread Chucks and Flex Hoses. For Road and MTB use. Colour: GOLD