The GSMP is a 14 inch. mounting post with an RMAA adaptor. Used in all Gibraltar’s Stealth set-ups, this post can help to create low profile custom rack set ups, or act as a tube extender for auziliary snare drums, electronics, acoustic drums, and cymbals. It comes with nylon adaptors to fit 3/4 inch., 7/8 inch., and 1 inch. diameter down tubes.