Trimax THEX5040 Combo Set - THEX Super Chain 5' x 10mm + MAX40 Disc U-Lock Large hexagon shaped 10 mm links Durable NYLOMEX sleeve protects against scratches; Durable PVC sleeve covers chrome steel shackle to prevent marring and scratching Hardened solid steel lock prevents prying, sawing and hammer impacts Withstands over 6 tons of pull force and 11 tons of cutting force Type B key, which is an ultra secure wise wafer key. Lock core design provides the highest degree of protection against picking. Includes 2 keys.