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Anti-two-block (ATB or A2B) warning systems are used to warn or prevent the crane operator from two-blocking the crane. Two-blocking is a dangerous condition where the hook block is raised until it contacts the boom tip. Without a proper crane A2B system, a two-block can cause expensive damage to the crane boom, personnel, and surrounding property.

Anti Two Block DEVICES

ENSURE CRANE SAFETY WITH ANTI TWO BLOCK (A2B) DEVICES

ATB devices are the most basic operator aide every crane should have. We offer reliable RaycoWylie brand wireless and hardwired ATB systems to fit every type of crane and application. The RaycoWylie model R147 and model R140 Anti two-block (ATB or A2B) warning systems have a superior design with a long history of proven performance and reliability. Order your anti 2 block device today!   

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