This is a Variable Rate Speed Control Valve from Robart. This is used to vary the rate at which a pneumatic retract functions. FEATURES: Red anodized aluminum, brushed aluminum, and brass construction. INCLUDES: One variable rate control valve. One instruction manual. REQUIRES: Assembly onto kit. Rate adjustment. SPECS: Length: 53.3mm (2.099") Width: 14.3mm (.562") Overall height: 24.0mm (.946") COMMENTS: This valve has through-the-bulkhead style mounting, and controls how fast your retracts move in both directions. Each adjustment screw has a lock nut to hold it at a setting once it"s adjusted. pjm 4/20/02 ir/kh