The 481 Studio Dolly boasts adjustable cable guards for smoothing out studio floor litter, plus a reinforced centre hub with collapsible box tubing arms. New, smooth action castors, and a sturdy wheel lock ensure the Studio Dolly 481 runs smoothly and surely under all Miller ENG, EFP and HD tripods. Collapsible arm design also lets the 481 glide through doorways unhindered.