Drive Medical Nitro O2 Tank Holder for exclusive use with Drive’s Nitro rollator. The Oxygen Tank Holder accomodates the most commonly used tank sizes (ML6/A tanks, M4/A tanks, M9/C tanks, M6/B tanks, M15/D tanks). It conveniently attaches to the Nitro’s front end without affecting any of the Nitro’s functionality. The product weight is 1.7 lbs. The standard tank holder have dimensions of 19.5" (W) x 7.5" (L) x 11" (H) while the heavy duty tank holder have dimensions of 24" (W) x 7.5" (L) x 11" (H).