This is an 7' Interfit Two Section Boom Arm with Counterweight. It attaches to your boom stand via its locking swivel. It has one telescopic section that includes a removable standard (5/8") stud that may be positioned straight, or at a 90° angle from the boom.
This boom and its 5.5 lb counterweight can handle a small - medium monolight with a 24 x 24" softbox on a 10' stand at maximum extension.