~ more compact trolley is 50% lighter than competitive trolleys, yet every bit as tough ~ negotiates radius curves as tight as 7 to 10 inches ~ made of highest quality rolled steel ~ unique double row, ball bearing wheel ......~ more compact trolley is 50% lighter than competitive trolleys, yet every bit as tough ~ negotiates radius curves as tight as 7 to 10 inches ~ made of highest quality rolled steel ~ unique double row, ball bearing wheel design for greater wear capacity ~ larger v-bars available for wider flange adjustment ~ bearings prepacked with lifetime lubricant ~ exclusive dial-fit collar quickly adapts trolley to wide range of beams and patented rails ~ lifetime warranty