"This Roughneck Manual Geared Trolley is ideal for use in garages, workshops, warehouses and other areas where machines are installed or where cargo is lifted, especially places without power equipment to do the work. Mount on wide-flange H-beams, standard I-beams, or curved tracks. Adjustable Yes, Beam Height in. 4-19, Capacity lbs. 6,600, Flange Width in. 4 3/8-6, Includes Sealed ball bearing wheels, Material Type Steel, Works With Wide-flange H-beams, standard I-beams, or curved track, Finish Type Powder-coat, OSHA Approved No. Fits 4 3/8in. to 6in.W flange All-steel construction for durability and wear resistance Trolley guards ensure extra safety Collars can be adjusted to fit a wide range of beam widths Hardened axles and wheels are lubricated for durability Easy and smooth operation over straight or curved track Easily attaches to hoists for loading or positioning Hand chain gear system provides precision-load spotting Rugged side plates ensure 10ft. hand chain stays in the track Fits beam height 4in.-19in. Tested at 150 capacity"