20x2.125 Studded Knobby BMX Tire by Duro - Black Coaster Brake They have a flush bolt

They have a flush bolt head on them

6-bolt Disc front and rear

Color: White w/ machined sidewalls

The Profile Gun Drilled Hollow (GDH) 19mm 48 spline crank axle is a great way to take a large chunk of weight off of your bike without sacrificing a great deal of durability

20x2.125 Studded Knobby BMX Tire by Duro - Black Coaster Brake They have a flush boltThis is one (1) Duro Studded Knobby Tread Pattern Tire. This tire tread pattern is HFT 851. It is very similar to the type of tires that were used on many bikes made in the late 70's and early 80s. Note: This tire DOES NOT have metal studs. "Studded Knobby" is the tread pattern. Color: All Black Note: We ship tons of tires, and we do ship them folded in a figure 8 unless a request is made to have them shipped flat. If requested, an additional shipping