Boron Alloy lasts 86% longer than the standard Rockwell 56 Square Alloy Tire Chains. 7mm Boron 10B21 Tire Chains do not have cams on the side chains so adjusting the overall length of the tire chains could obtain a better fit than the 5.5mm Square Alloy Forklift Tire Chains. Please note:Due to forklift tire variances, tailoring is normal and expected. OptionalTire Chains Tensioner is recommended for maximum life and performance of tire chains. Please note:Due to forklift tire variances, tailoring is normal and expected. OptionalTensioner is recommended for maximum life and performance of tire chains. 5.5mm Square Alloy cross chains allows for added traction and durability. Square link provides the traction of the v-bar without the added profile of a welded v. The square design wears more evenly, unlike the twisted link that wears only on its high points. For easier installation of Square Straight Link Chains see our Sno-Chain Ramps . Optional rubber or spring tensioners are recommended. If your tires are deep lug, mud, load range E, or AT tires, please contact us prior to purchasing. Square link tire chains are more durable and provide increased traction compared to twisted link snow chains. Twisted Link Tire Chains wear the high point of the twist which is a small fraction of an inch. Straight link tire chains wear the entire length of the link which could be an inch or more. This distributes the stress and wear of the chain. For Traction, the square alloy tire chains uses square rod which almost equals the traction of a v bar for ice. Twisted link is round rod. For off road conditions, square also provides additional traction since the links not nestled within each other like the twisted link. This provides more profile on the face of the tire for more traction.