The Krytac Magazine M4 Midcap 150rds was developed to be the perfect choice for Krytac gun owners who are looking for a reliable, high-capacity magazine for their M4 or other compatible airsoft rifles. This midcap magazine offers a 150-round capacity, which is great for extended airsoft skirmishes, and is constructed out of durable polymer that resists wear and tear. The magazine is easy to load, and the rubberized base grip provides a secure fit in the rifle's mag well. You may want to consider PTS magazines for high feed rates and higher capacities.