If you shoot USPSA Limited, Limited Optics, or Carry Optics, every magazine has to fit the official 141.25 mm gauge. The Henning Group SAFE CHECK 141 mm gauge lets you confirm each mag fits safely inside that limit before you ever stand at equipment check.
Each SAFE CHECK gauge is machined approximately .010" under the 141.25 mm maximum, so a magazine that drops in cleanly has real margin — not a “barely fits at home” pass that fails on a different gauge at the match. A built-in side guard keeps the magazine parallel in the gauge for a true, repeatable reading.
When you load every legal round into a 141 mm setup, small differences stack up fast. Tubes vary. Basepads and extensions vary. Even official gauges vary. Checking with margin is the responsible move.
Running Henning extensions to hit max capacity? Gauge them with SAFE CHECK, then keep each tube/basepad/extension together as a matched, legal set. Shop the Henning extensions we stock:
Henning USPSA magazine extension for CZ 75 and Shadow 2.
Henning CZ P-10 PLUS 3 USPSA magazine extension.
Henning magazine extension for the CZ Tactical Sport.
Henning magazine extension for full-size Glocks.
Henning Group Glock 19/26 Plus 5 mag extension.
Henning Group Smith & Wesson M&P magazine extension.
Browse all Henning magazine extensions ?
