This fully functioning remote controlled 8421 Mobile Crane is a revised version of my previous 8421 Crane. Many mods went into this one. My main goal was to have the crane section rotate 360° which I accomplished but ended up almost revising the whole crane. This required mods to both sections of the crane. This crane has 2 battery packs, 4 IR recievers, 1 XL motor, 4 Remote IR Transmitters and 6 M motors. This Crane is fully functioning and fully Remote controlled through IR recievers using all Lego power functions. It has lights and 2 linear actuators. As before, the pneumatics just don't function in a way to be used on this Moc. The Boom is lengthened from original to 36" long once fully extended. The crane moves forward, backward, steers right & Left, stabilizers drop & lock and retract, boom raises lowers, extends and retracts, and hook raises and lowers. Again all functions using Power functions IR equipment. This Moc weighs in over 7 pounds. I hope to soon have video of this Crane in action.