Description Robart 3/8" (9.5mm) diameter are the best replacements for wire landing gear. They are suitable for most airplanes weighing 4 to 14 pounds. With real functional oleos and torque links, they can be used on grass or paved airfields. No more bent wires! The RB-650 struts come with easy to use 5/32 inch (4mm) and 3/16 inch (4.8mm) dia. wire adapter bushing.