Trek Boone 2020 Headset Bearing Kit (2 x W540243)

Trek Boone 2020 Headset Bearing Kit

Trek Part Number: 2x W540243

Upper Bearing – ACB4051K – (40 x 51 x 6.5 – 36/36)

Lower Bearing – ACB4051K – (40 x 51 x 6.5 – 36/36)

The black oxide coating on these bearings helps prevent rust for as long as possible whilst being a good bit more budget friendly than full stainless steel. A wider range of bearings are available in black oxide than stainless steel.