Side Drive Motor Driven Trolley Hoists is used for horizontal load movement and are available in single or variable speeds up to 106 fpm. The trolley gearbox is the same simple, reliable, proven design that is used on all electro lift hoists. The features include trolley brake, ballast resistors, soft starts and stops, & variable frequency drives. They have trolleys, which have the ability to ride on specialty tracks from a 2″ flange width.