These are the Scale Retract Units Designed Specifically for the Top Flite P-47 Giant Scale Kit. This is an Offset Retract Unit that pivots on the outside instead of the inside of the unit. The hinge point is on the front of the retract unit. FEATURES: Fully functional Oleo Strut. Offset Axles to provide a scale wheel stance. Offset Unit advantage mounts between the wing ribs and stengthens the wing even more. Frame made of "glass-filled nylon, aluminum and aircraft steel Positive Up and Down Locks. INCLUDES: Axle hardware to mount the wheels to the retract struts. One Left Retract Assembly One Right Retract Assembly REQUIRES: 1-ROBQ2367 4-way valve 1-ROBQ2368 fill valve 1-ROBQ2369 tubing 1-ROBQ2392 large pressure vessel This Will Also Require Tee-Fittings (ROBQ0223) and Retaining Nuts (ROBQ2370). Recommended that 5" Wheels are the Maximum size that can be used. SPECS: Width of retract unit: 2", (including the strut: 3.25") Length of unit: 3-5/8" (not counting the cylinder) Height of unit: 1-1/2" Diameter of Strut: 1/2" Length of Strut: 9" Weight Bearing Capacity: 22 to 24 pounds. Weight per pair: 23.2 oz. COMMENTS: This unit is recommended only for the Giant P-47 Thunderbolt kit from Top Flite. This is the New updated Version. BOX DIMENSIONS: 3.88" W. X 3.75" H. X 12.25" L. BOX WEIGHT: 1.77 LBS. RobartPart ROB622-P47