Loads all 9mm Luger, .357 Sig, 10mm, .40, and .45ACP cal. single and double stack magazines., including 1911 mags, of all manufacturer; Also loads most .380ACP double-stack mags; One size fits all. No inserts, spacers or adjustments at all; Easy loading; the rounds just drop in with no fingers pushing or pressing them; No more pain! Load hundreds of rounds painlessly; Protects your fingers and mags; Up to one round per sec. loading rate. 1/3 the time loading several mags compared with thumb loading; Fits in hand and pocket, weighs only 72 grams (2.55oz); Highly durable