Confirmed Fitment
Sig 239 Magazine Loader
The Sig 239 is confirmed to fit the Super Thumb ST3, the loader ADCO builds for single-stack magazines. It loads Sig 239 magazines faster and with far less thumb strain — a purpose-built tool, not a one-size-fits-all compromise.
Why single-stack magazines pinch
Single-stack magazines have narrow feed lips and a firm spring in a thin body, so the top rounds bite back at your thumb. The Super Thumb seats each round without fighting the feed lips, which is easier on your hands and faster round after round.
Your Fit
Super Thumb ST3
Single-Stack
Width
1.47" (37.3 mm)
Height
0.65" (16.6 mm)
Sig 239 loader — common questions
Which Super Thumb fits the Sig 239?
The Sig 239 is a confirmed fit for the Super Thumb ST3. It appears on ADCO’s verified Super Thumb fit chart as an exact match.
What kind of magazine does the 239 use?
The Super Thumb ST3 is built for single-stack magazines, which is the class the Sig 239 uses.
Will the same loader work for my other Sig pistols?
Often, yes — many Sig models share the same magazine class. Check the other Sig fits listed below, or use the Model Finder to confirm your exact model before ordering.
Is the Sig 239 fit guaranteed?
Every Super Thumb is backed by a lifetime warranty. If you’re not certain, confirm with the Model Finder or call ADCO at 781-935-1799 before you order.
Not 100% sure? Confirm before you order.
Super Thumb loaders are model-specific. Use the Model Finder to double-check your exact firearm and magazine, or call ADCO Arms and we'll confirm the right loader for your Sig 239. Every Super Thumb is backed by a lifetime warranty.