The PMAG 10 Gen M3 is the standard

The Magpul PMAG 10 Gen M3 magazine is a 10-round 5.56x45mm NATO (.223 Remington) polymer magazine for AR-15/M4 compatible weapons. Designed to work flawlessly every time no matter what conditions you encounter, this is a great replacement or spare AR-15 magazine for areas that do not permit high-capacity magazines.

Along with an expanded feature set and compatibility, this PMAG 10 magazine incorporates new material technology and manufacturing processes for enhanced strength, durability and reliability to exceed rigorous military performance specifications. A redesigned bolt catch notch in the rear of the magazine provides increased bolt catch clearance, while an over-travel stop on the spine helps ensure the magazine will not over-insert on compatible weapons.

Magpul PMAG 10 Gen M3 magazine Specifications and Features:

Manufacturer Number: MAG559BLK
Magpul PMAG AR-15 Magazine
Caliber: .223 Remington, 5.56mm NATO
Capacity: 10 Rounds
Body Material: Polymer
Spring Material: Long Life USGI-Spec Stainless Steel
Follower Material: Self Lubricating Polymer
Baseplate Material: Polymer
Constant Curve Design
Anti-Tilt Follower
Flared Baseplate
Ribbed Griping Surface
Over-Travel Insertion Stop on The Spine
Paint Pen Dot Matrix Panels on The Bottom of The Body for Marking
Non-Windowed
Made in the U.S.A.
Finish: Black

Fits:

Most AR-15/M4 platforms
HK 416
HK MR556A1
HK M27 IAR
British SA-80
FN SCAR MK 16/16S