Description
Use this interface to pay for miscellaneous non invoiced listed items or gratuities.
This interface to pay any outstanding service balances, odd nonlisted item purchases, or if you simply want to leave a donation, this is the place to do that.
Thank you!
Use this interface to pay for miscellaneous non invoiced listed items or gratuities.

Installation Video for 1.5″ Picatinny rail on the Umarex Gauntlet forearm.
Hajimoto Flex Reg on 22ci Aluminum 3K for the G1
Introducing a Hajimoto Productions Exclusive offer!
22ci/360cc/.36L Aluminum Tank 3000PSI
Newly redesigned unit
Now has a high pressure and low pressure burst discs!

Flex 22 Configuration For Generation 1 Gauntlet .177/.22 Cal
Stock .177/.22 | 3000/1100PSI Regulator
Flex 22 .177/.22 |3000/700 to 1500PSI
Flex 22 Configuration For Generation 1 Gauntlet .25 Cal
Stock .25 | 3000/1900PSI Regulator
Flex 22 .25 | 3000/1500 to 2300PSI
If you are looking to add an externally adjustable reg to your Gauntlet 2, take a look at swapping your current fixed reg to the Flex reg found HERE
Installs on the Gauntlet with minor tank shroud modifications. (The Gauntlet 2 is shown to give an idea of what modification needs to happen and that is simply a hole drilled in the bottom of the plastic tank shroud for the fill nipple.

A 22ci aluminum 3000PSI cylinder with externally adjustable Ninja Flex Reg for your Umarex Gauntlet1! The volume of air in these 22ci tanks over the 13ci is mind-blowing!
The diameter of the tank is 54-55mm across so a modification to the forearm is required on a Gauntlet 1. I do offer a tank shroud modification service for Gauntlet 1 owners that can be added to a build or provided as a mail-in service.
The Gauntlet 2 forearm slide right over without any issue. Only one access hole needs to be drilled so the fill port is accessible at the bottom.
Consider picking up our extended foster fill adapter to make coupling and filling a breeze.
The Power Flex Combo allows the user to externally adjust the regulator output pressure on the fly with an adjustment range of 800PSI!
When installing the Flex 22 on the Umarex Gauntlet. Tighten the degassed tank and regulator assembly fully to the rifle, then back it off until the fill port is on the bottom and the gauges are left and right. Now fill the bottle with air and all will tighten up solid. Proper alignment will be achieved before the 360° maximum rotation limit is realized.
Comes with a dedicated Spanner Wrench for power adjustment. MADE IN THE USA!
Because of practical limitations, regulator output will be +/- 50PSI (3.5bar) within the requested output.
Gauntlet STK
THIS ITEM IS NOT DESIGNED FOR THE GAUNTLET 30
IT HAS ITS OWN HAMMER PRELOAD ADJUSTER STOCK
The single largest performance increase modification item for the Gauntlet. The Super Tune Kit allows complete power adjustment, opening the possibility of higher or lower foot-pounds (FPE) for whatever the user desires. Do you need only 5FPE? No problem back off the adjustment using a 5/64″ allen wrench and you are only delivering 5FPE and will realize over 200 shots on a stock bottle fill of 3000PSI!
Want 27-30FPE for dropping that 20lb trash bandit, no problem, crank up the adjuster using a 5/64″ allen wrench and you instantly have the power necessary for either long range or high energy delivery on target. The use of a chronograph is required to know the rate of travel of the projectile. (Power examples given are the .22 caliber version Gauntlet 1)Ā
For the Gauntlet 1 and Gauntlet 2. Be sure to select the proper generation, as there is a difference, and improperly selected kits are not returnable.
BE SURE TO SELECT THE CORRECT GENERATION GAUNTLET
CONTENTS:
Be sure to follow my written instructions in the document below.
Use the video to install but follow these written instructions to adjust and tune the STK:
Written Detailed Tuning Instructions for the STK
More details below.
Always read the content below because any revised instructions, video, photos, or other links will be there.
Copyright All rights reserved Hajimoto Productions LLC 2025
Proudly powered by WordPress . Theme: multipurpose shop by eDataStyle.Please be sure to understand our return policies prior to making your purchases. All products offered on our website are intended for use on airguns only. It is a violation of Federal Law to use a product in a manner inconsistent with its intended labeling or use. It is the purchaser's responsibility to know the ordinances and laws of their state or county and to fully comply with them. Dismiss