Rounded outer sidewall. Fits Slot It 17 x 10 Wheels (SIPA19, SIPA10) including stock rear wheels on Nissan R390. Also fits Carrera C6R Race Liveries (not Street Versions), Mercedes DTM, Audi DTM, Porsche RS Spyder ALMS, Ninco pro-race 17" wheels, ProSlot Toyota GT1, Porsche GT2, SCX Ferrari 360 Modena.