PN#034084  SKU#11897  Limiting & Quick Release Valve. LQ-2 Style. Limits front axle service brake application by 50% and service as a quick release valve for that axle- commonly found on pre-121 (pre-1985) vehicles. 3/8″ NPT Supply, Delivery and Exhaust Ports. 1/4″ NPT Control Port. 19/32″ diameter mounting holes at 1 1/2 on center.