This is a 7/16" in dia. Straigth Robostrut from Robart. Strut is made of high grade aircraft material and is TST certified. Strut is also a fucntional oleo type. This is designed for planes weighing a max of 15lbs. INCLUDES: 1 Straight robostrut 1 wheel axle 4 set screws 1 3/16" bushing 1 1/2" adapter sleeve 1 instruction sheet SPECS: Strut length: 7-1/8" Axle length: 1-1/2" Dia: 7/16" Dia: 3/16" COMMENTS: By using the 3/16" bushing the strut can be used with a 3/16" dia. music wire mount. If the custumer doesn"t use the 3/16" bushing s/he will need to use the 1/2" adapter sleeve. This can be used with either a fixed gear or a retract setup. 2-5-97 djg