Patent ID: 7128494

Claim:
An assembly kit comprising: a caster having an elongated stem including a groove disposed near a distal end of the stem, and a friction ring having a substantially circular cross-section, the friction ring being disposed at least partially within the groove; a tubular framing member for a base having a lower wall and an upper wall, the tubular framing member defining a cavity between the lower wall and the upper wall; a first aperture disposed on the lower wall, the lower wall having a first substantially frusto-conical shaped area extending inward into the cavity, the first shaped area defining a perimeter of the first aperture; and a second aperture disposed on the upper wall such that the second aperture is substantially aligned with the first aperture relative to a vertical axis, the upper wall having a second substantially frusto-conical shaped area extending outward relative to the upper wall, the second shaped area defining a perimeter of the second aperture and the second aperture having a diameter; such that as the stem is moved upward toward the first aperture, the first shaped area compresses the friction ring into the groove a sufficient distance to permit the stem to pass through the first aperture, the friction ring expanding after exiting the first aperture; and as the stem is moved toward the second aperture, the second shaped area compresses the friction ring into the groove a sufficient distance to permit the stem to pass through the second aperture, the friction ring expanding after exiting the second aperture such that an outer diameter of the friction ring is larger than the diameter of the second aperture to prevent the stem from exiting back through the second aperture by gripping the upper wall of the tubular framing member to support the stem without the use of an insert.