Ultimate Support Ultimate Studio Series Microphone Boom Stand w/Adjustable Counter Weight (MC125) rollerblade-style caster wheels for super smooth movement in all directions but lock in both rotating direction for zero movement when desired. The MC-125 features a 5.75 lb. die-cast counterweight that is easy to adjust for just the right placement. The MC-125 has been called the "most adjustable studio boom on the market." It ranges in height from 52" to 83" and the boom can extend from 35" to 61" to meet any studio's needs with perfect placement every time. Stand Height (with Casters): 51.5" - 82.75" (1308 mm - 2102 mm)Boom Length: 35" - 61" (889 mm - 1549 mm)Caster Diameter: 3.75" (95 mm)Base Diameter: 22.5" (572 mm)