The CRL Heavy-Duty Full Surface Roton Hinges are made of high strength aluminum with a full length rolling gear profile to align doors perfectly from top to bottom. They feature twice the standard, special self-lubricating, polyacetal load bearing blocks that deliver a smooth, almost floating operation on even the heaviest doors. Hinges are completely secure because all mounting hardware is hidden when installed. Hinges are easy-to-install and come with instructions and all necessary hardware for mounting. Available in clear satin anodized or dark bronze duranodic finishes. These Heavy-Duty Hinges are stocked in lengths of 83" and 95" (2.10 and 2.41 m). Replacement Screw Packs are also available.