Rhino-Rack 2500 Leg Spacer - 34mm - 2 Adaptors/6 SpacersThe RLKS4 spacer blocks are used to level a 3 bar roof rack system on a vehicle such as a pickup that may have rear posts or a cap topper rack system. Attached between the Rhino Rack 2500 leg and either a Rhino Rack Heavy Duty or Vortex cross bar, this set of spacers will raise the cross bar 34mm in height. Glass Reinforced Legs Provide Extra Strength Support 8 Spacer Bocks For A Maximum Height Of 34mm 2 x M6 x 55mm