Can the Friction Knob UMS be attached to a table, bed or wheelchair? Ed Clausen February 11, 2021 18:01 Updated Yes, the Super Clamp allows mounting to flat or round (tubular) surfaces up to 2” in size. Related articles How much weight can the Latitude hold? Does the Friction Knob UMS swivel to allow easy access in and out of a wheelchair? Comments 0 comments Article is closed for comments.