BMXGuru 35T Aluminum Spider & 4-bolt Chainring Combo - Silver over Blue - USA Made Sz 18 It is made out of

It is made out of 6000 series aluminum and is approximately 400mm long

It features densely packed small knobs which provide good bite

is enough of a description to get you the correct headset

This is an aluminum post with a 2-bolt

BMXGuru 35T Aluminum Spider & 4-bolt Chainring Combo - Silver over Blue - USA Made Sz 18 It is made out ofBMXGuru 35t chainring spider combo. 35t anodized Silver aluminum chainring 23. 8mm bore hole Fits 1 piece cranks or 19mm or 22mm cranks with adapter (not included) Blue Spider, 104mm BCD 4 bolt Chrome plated bolts 3 32" teeth size works with 3 32" and 1 8" chains MADE IN THE USA! For 19mm adapter click HERE!