This 4-Way Control Valve Allows Modelers to Control Retract Speed of the Left and Right Side of a Pneumatic Landing Gear System Separately. FEATURES: Duplicates the Uneven Way Landing Gear Retracted on Older Aircraft. Four Separate Adjustments for Left and Right Gear Up and Down. INCLUDES: 4-Way Control Valve Only SPECS: Length: 1-3/4" Width: 1-7/16" Thickness: 3/8" COMMENTS: This valve Works with Any pneumatic retract System. ir/jl