Already maxed out your 7-round tube? This titanium magazine extender cap threads on in seconds and pushes capacity further — no heat gun, no modifications.
KEY FEATURES & BENEFITS
+1 cap: 8+1 on a standard M4, 6+1 on an SBS
+3 cap: 10+1 on a standard M4, 8+1 on an SBS — the highest tube-fed capacity available for the platform
Precision CNC machined from aircraft-grade titanium and Cerakoted in the USA
Replaces your existing OEM magazine cap — no permanent changes
Includes the correct 8-round or 10-round spring for your chosen capacity
Black, H2O, or FDE Cerakote finish options
Lifetime warranty
PRODUCT DESCRIPTION
Standard M4 owners who've already hit their 7-round ceiling, and SBS owners working with a shortened tube, both run into the same wall: no more room. This cap gets around it by adding physical tube length at the muzzle end, in titanium to keep the added weight as low as possible.
Installation is a straight thread-on swap for the OEM cap — no tools, no gunsmithing. Building capacity from scratch instead? Pair this with our 7-Round Magazine Tube or 5-Round Magazine Tube.
FULL SPECIFICATIONS & INSTALLATION
Capacity by configuration: Standard M4 (7rd tube) — 8 rounds with +1 cap, 10 rounds with +3 cap. SBS (5rd tube) — 6 rounds with +1 cap, 8 rounds with +3 cap.
Springs included: the +1 cap ships with an 8-round spring; the +3 cap ships with a 10-round spring.
Color notes: Black is a custom dark gray Cerakote that deepens further with a light coat of gun oil. H2O is a custom titanium-toned Cerakote made to closely match the factory H2O/Titanium finish. FDE closely matches OEM flat dark earth M4s.
Installation: remove the existing magazine cap and spring retaining ring, and thread on the extension — no heat gun, or gunsmithing required.
COMPATIBILITY
Original Benelli M4 / M1014 with 7-round tube, and SBS configurations with 5-round tube. May fit on clones. Note: capacity-increasing products do not ship to NJ or MA.
Squeeze more rounds out of the tube you already have — order your +1 or +3 cap now.
