2 arms that fit on right-type rods, instead of the usual hook at the end of the arm, there are parts where the shelf is fastened with screws. Very useful for shelves that do not fit the common dimensions of the arms (e.g. 15, 20, 25, ....) and also more aesthetically pleasing for anyone who does not want the arm to be so visible at the end of the shelf.

Very good product, sturdy construction and durable.
(The arm with the hook at the end arrived, not the one you screw onto the wood)