Super Slim Lite Wheels were designed for most ARF's that need larger dia. treaded wheels to taxi and take-off from grass fields. They are slim to fit onto short and small diameter axles. The axle hole is (3.0 mm) 0.118in dia. and a width of (16.4 mm) 0.645in. They are lightweight at 8.8 grams/ea for the 275SSL and 10.2 grams/ea for the 300SSL.