Confirmed Fitment
Keltec 40 Magazine Loader
The Keltec 40 is confirmed to fit the Super Thumb ST1, the loader ADCO builds for standard double-stack service-pistol magazines. It loads Keltec 40 magazines faster and with far less thumb strain — a purpose-built tool, not a one-size-fits-all compromise.
Why loading these magazines is a fight
Double-stack magazines get progressively harder to load as the spring compresses — the top few rounds are where thumbs give out. The Super Thumb pushes each round straight down against that spring tension for you, so topping off to full capacity takes seconds instead of sore thumbs.
Your Fit
Super Thumb ST1
Double-Stack
Width
1.29" (32.5 mm)
Height
0.86" (21.9 mm)
Keltec 40 loader — common questions
Which Super Thumb fits the Keltec 40?
The Keltec 40 is a confirmed fit for the Super Thumb ST1. It appears on ADCO’s verified Super Thumb fit chart as an exact match.
What kind of magazine does the 40 use?
The Super Thumb ST1 is built for standard double-stack service-pistol magazines, which is the class the Keltec 40 uses.
Will the same loader work for my other Keltec pistols?
Often, yes — many Keltec models share the same magazine class. Check the other Keltec fits listed below, or use the Model Finder to confirm your exact model before ordering.
Is the Keltec 40 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 Keltec 40. Every Super Thumb is backed by a lifetime warranty.