DURAMAG Speed™ magazines are a truly improved USGI magazine. DURAMAG Speed™ bodies are constructed of 6061-T6 aluminum and are type-III anodized to the mil-spec. This battle-proven magazine is lightweight, durable and feeds every time. DURAMAG SPEED™ mags have been the magazine of choice for OEM, Law Enforcement and Military Units throughout the world and are safe for extended storage while loaded. DURAMAG™ will not flex or swell like polymer.