The Ultimag 30R is a 30-round 5.56x45 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. - Advantages: - 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 - Compatibility: 5.56x45 NATO (.223 Remington) M16/M4/AR15