Geissele 13.5" M-LOK MK14 Black Super Modular Rail 05-573B

Geissele 13.5" M-LOK MK14 Black Super Modular Rail 05-573B is Geissele's answer to shooters who wanted MK16-level rigidity in a noticeably slimmer package. It's not a trimmed-down version of another rail - it's a distinct design, built specifically to reduce diameter and height without giving up the lockup Geissele rails are known for.

At 2.02" tall with a 1.27" inner diameter, this Geissele Super Modular Rail MK14 measurably reduces the cross-section your support hand has to wrap around compared to the standard MK16 or MK4 lines, which matters more than people expect on longer builds where hand fatigue actually shows up. It's machined from 7000-series aluminum and mounts through the same 2.25" Geissele barrel nut design used across the lineup - long surface contact with the receiver, so the rail stays straight and true even after repeated disassembly.

M-LOK slots sit at 3, 6, and 9 o'clock, and a full-length Picatinny top rail handles optics and iron sights. This MK14 rail comes in around 10 ounces bare, 11.5 with the barrel nut - genuinely light for a rail this length, and the slim profile makes the weight feel even less noticeable in hand.

Key Features:

• 13.5" free-float length, full-length Picatinny top rail
• M-LOK slots at 3, 6, 9 o'clock
• 7000-series aluminum, Type III hardcoat anodized
• Proprietary 2.25" Geissele barrel nut
• Height 2.02", inner diameter 1.27", outer diameter 1.52"
• Weight: 10 oz bare, 11.5 oz w/ barrel nut
• Black finish
• Fits mil-spec AR-15 upper receivers

If the standard-diameter rails have always felt a bit bulky in hand, this 13.5" Handguard is the fix - same rigidity, meaningfully slimmer grip. Reference Geissele MK14 Rail, M-LOK Rail, or Geissele SMR Rail for the broader lineup.