MechArmy RU02 Review: A Titanium EDC Multi-Tool With a Built-In Caliper

Introduction

Small titanium multi-tools are easy to love, but harder to be surprised by. Most follow the same recipe: a pocket-friendly body, a small blade, maybe a bottle opener. The MechArmy RU02 takes a different route by adding something rarely seen on an EDC tool at all: a real sliding caliper.

The RU02 is currently running on Kickstarter, and it comes from MechArmy, a brand known for a large catalog of intricate titanium EDC gear, including pens, knives, whistles, compasses, a flashlight, and an unusually wide range of connectors and carabiner-style keyring pieces.

What Makes the RU02 Different

The RU02 is essentially two tools in one compact titanium body: a knife and a caliper. Both work exactly the way you would hope, and neither feels like an afterthought.

It is also worth noting this is not MechArmy’s first caliper tool. The earlier RU01 offers the caliper without the blade. The RU02 answers the obvious follow-up request by adding a knife to the same formula.

The Scalpel Blade

The blade is the first standout. Instead of a small utility blade, the RU02 uses a large size 24 scalpel blade, noticeably bigger than what you typically find on similar pocket tools. The Kickstarter package is advertised to include at least 10 blades, and because size 24 is a traditional scalpel size, replacements are easy to find. Blades are disposable, so you simply swap them out when they wear.

The opening mechanism is non-locking and runs on what appears to be ball bearings, and the action is silky smooth with full coverage through the entire travel. In the hand it feels solid and safe while still allowing intricate cutting work.

The Built-In Caliper

The caliper is the part you will not find elsewhere. A sliding unit sits in the body: press the latch to release it, slide it out to a captive stopping point, press the latch again to extend it to full length, and you can even remove it completely for standalone measuring. To stow it, press down, slide it back, and it locks into place.

Accuracy holds up well in use. Measuring a dead-on half-inch finger driver, the RU02 matched the reading of a digital caliper, which is exactly what you want from a measuring tool. It is made from solid titanium and feels hefty for its size.

Who Should Buy It

If you regularly reach for calipers in arts, crafts, or workshop work, having one permanently in your pocket is genuinely convenient. Add in the replaceable scalpel blade for cutting tasks and the RU02 covers two jobs that most EDC tools ignore entirely.

Conclusion

The MechArmy RU02 stands out in a crowded EDC market by doing something different rather than repeating the usual knife-plus-opener formula. The smooth non-locking scalpel action, the accurate titanium sliding caliper, and the solid in-hand feel all point to a well-executed idea. If you have been waiting for an EDC tool that cuts and measures, this one is worth a close look.