Fab Defense ULTIMAG Window Magazine FDE M16/M4/AR15 5.56mm NATO Rifle Magazine - 30 Rounds - The Ultimag 30R is a 30-round 5.56mm NATO (.223 Remington) polymer magazine for AR15/M4 compatible weapons, with transparent windows for rapid visual identification of remaining rounds The Ultimag 30R provides a strong, durable, and reliable magazine solution using high grade materials. Multi-textured surface for enhanced grip when handling and reloading Unique floor plate for versatile coupling options Disassembled by hand, no tools needed Long-lasting cataphoresis-coated spring for ideal corrosion protection Hybrid AK style spring design prevents tilt Unique internal design for smoother, more reliable feeding Low-friction follower for increased reliability Durable, lightweight, impact and crush-resistant reinforced polymer body Long-lasting spring design for extended duration in loaded storage Round-level windows and indicators on both sides indicates from 10 to 30 Extended floorplate for improved magazine handling with gloves and gear Compatible with double and triple mag pouches Over-travel protection, stops on the follower for reliable spring operation