Cornerstone Safety Thumb Ledge for Ruger® Mark IV


$49.99 - $54.99
(20 reviews) Write a Review
0.30 LBS
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At a glance:


  • Oversized, 1911-style safety ledge
  • Enhances factory safety
  • Improves hand placement for better grip, control

Whether you’re a competitive shooter working to improve your speed and accuracy or a weekend plinker looking for better control over your pistol, a strong, proper grip is key. The new Cornerstone Safety Thumb Ledge from TANDEMKROSS is the ideal upgrade to boost your control!


Now available for the MKIV™, the oversized, 1911-style Safety Thumb Ledge, made from anodized aluminum, enhances the external factory safety, without modifying the internals of the safety mechanism. This drop-in part is easy to install and does not change the internal components of the gun. Installation of the Cornerstone Safety Thumb Ledge for Ruger® MKIV™ is also a great opportunity to remove the factory ambidextrous safety, which can pinch some users' fingers while shooting.

The aluminum Cornerstone safety ledge offers an ideal thumb placement for a secure grip and provides consistent hand positioning and helps to control muzzle flip. This is one of the best Ruger® MKIV™ accessories for competition shooters. Get your Cornerstone Safety Thumb Ledge today and lay the foundation for a better grip!

Please note: The Cornerstone installation utilizes a factory spacer included in your original box. This part is referenced on Page 23 of the original Ruger® manual. If you cannot locate this spacer, please contact TANDEMKROSS or Ruger® and we can assist you with locating one.

Supported Models:

  • Ruger® MKIV™ Standard
  • Ruger® MKIV™ Target
  • Ruger® MKIV™ Hunter
  • Ruger® MKIV™ Competition
  • Ruger® MKIV™ Tactical

Please note: Some modification of the grips may be required for proper fit on Hunter and Target models that use the target wraparound wood laminate grips with finger grooves.


Don't forget, all TANDEMKROSS products are Made in the USA and come with a LIFETIME guarantee!


WARNING: This product can expose you to chemicals including chromium, which is known to the State of California to cause cancer. For more information go to

20 Reviews

  • 5

    Posted by Ra on 12th Jul 2023

    Great for one hand shooting. Could do with a bit more surface area and sit higher, but I have big hands. Two handed grip its a bit low for my taste but it have a thumb ledge up front that works well for two handed grip. Easy install.

  • 5
    Cornerstone for Mark IV

    Posted by Nicholas on 18th Nov 2022

    Great product. My second one. I highly recommend Cornerstone to anyone who owns and shoots a Mark IV, 22/45 or steel frame. Installation is not complicated, follow Bill's video closely.

  • 5
    Safety lever

    Posted by Kendra w on 31st Oct 2022

    A must have! I love this!

  • 5
    Cornerstone Safety

    Posted by James Flagg on 7th Jul 2022

    I shoot competitions with my Volquartsen modified Mark IV Competition. This safety allows me to use my safety more during competitions because it is easier to release after the pistol is on target. It does take a little while to get used too but, dry practice took care of that.

  • 5
    Cornerstone safety thumb ledge for Ruger MKiv

    Posted by Mark on 14th May 2022

    Very trick product. It installed easily and looks great in the red on my pistol.

  • 5
    Safety Thumb Ledge for Ruger® MKIV

    Posted by Marty on 15th Apr 2022

    I wanted this so I could rest my thumb on the safety like I do my 1911s. Works like a charm. Quality product.

  • 5
    Nice add-on

    Posted by Nancy Stahl on 10th Mar 2022

    I like having a place to rest my thumb and to avoid accidentally putting the safety on. I have found it to be a little uncomfortable with my thumb. I believe this is more because I have a fairly long thumb and I have been doing a lot of dry fire. When I just use it for Bullseye shooting or having some fun at the range. Definitely a great upgrade.

  • 4

    Posted by Philip White on 11th Feb 2022

    A great safety replacement. It's fairly easy to replace if you use a punch to guide it into place. Just make sure you don't lose the spring when reinserting it. On the target model I found I needed to set the spacer upside down so that it would fit otherwise it spins. Other than that it's perfect.

  • 5
    Safety thumb ledge

    Posted by John Torres on 19th Jan 2022

    Great upgrade!