2 sealed cartridge bearings. Alloy dust cover with an internal O-ring for a snug fit and laser-etched Primo logos. Includes bottom race.
Upper bearing is standard 1-1/8"
Lower bearing is oversized 1.5"
Designed for Stranger's Ballast Evo frame, but will also work with a variety of MTB dirt jumpers with tapered head tubes.
*Compatible with TAPERED 1-1/8" to 1.5" integrated head tubes only.