Heavy duty MXZ Non-Sealed Mini Racing chains made for mini MX and SX racing. MXZ chains feature Chromoly steel construction with seamless rollers and bushings, and oversized special alloy pins for added strength. GB428MXZ1 Racing Chains are the strongest in their class giving you the best Value-Performance rating of any MX Racing Chain in the world today. Weighs in at just 2.21 lbs. per 100 links. 428MXZ1 Chain Specs: Tensile Strength: 6,070 lbs., Max CC Rating: 150cc Off-road, Max horsepower: 30 HP, Master Link Included: Clip type - Must use MXZ1 Specific Clip Link