These are great. The larger bubble is easier to see. Not getting caught or hung on anything as I expected.

Overall, these are solid, secure scope rings, but I don't really like where the level is placed. I have found that I am constantly afraid I'm going to snag it or bump it which would surely bust the level. I wish it was on top or bottom instead. Even reaching up to make an adjustment to my scope is kind of awkward because of how it sticks out. Other than that, the rings are solid and secure. I've always been pleased with Monstrum brand quality, but I'm not a fan of the level design.

This is not my first product made by Monstrum and their products never disappoint! I currently have several Monstrum scopes and red dots, and I really like their design and build quality. So far, I did not have a single issue with their products. The build quality of these rings seems to be excellent, it's on par if not better than Vortex products' quality in my opinion and at a fraction of the cost (like 3x cheaper!). They actually look very similar to “Deadlock” series with one exception - one of the rings has a small bubble level built-in in its upper right section. Having a bubble level is an excellent feature that helps to position your rifle properly and avoid tilting your rifle left or right, which can cause trajectory deviation especially when shooting at long distances. They are not as heavy as other rings I have but look and feel rock-solid. I didn't have any alignment issues with the rings, and the manufacturer states that there's no need to lap the rings due to precision machining. From my experience, it's absolutely true, but I'd still expect that some people, being very particular about the scope fit, are still going to lap them a bit, which is totally unnecessary. In my case, they were matched ideally and good to go out of the box and didn't need any lapping. Sturdy and locked in tight with no movement. Each ring has a recoil stop that guarantees that they will maintain zero alignment under the heaviest caliber recoil, no worries here. They are made of strong 6061 aluminum and have two locking screws on the Picatinny clamp for guaranteed secure mounting. Also, they use 6 steel locking screws to tighten the ring halves around the scopes tube, which gives it a better clamping power. End-to-end, they seem to provide a rock-solid mounting platform for even the heaviest and largest long-range scopes and will withstand high caliber recoil with ease. Great rings! The only feature that I'm missing in the scope rings setup is a QD mount, but it's not a biggie. This is a very solid and stable scope platform, and for the cost you can't go wrong. Solid 5 stars product, highly recommended!**TL;DR:**Monstrum Challenger series scope rings deliver excellent build quality, comparable to high-end brands like Vortex but at a fraction of the cost. A standout feature is the built-in bubble level for preventing tilt and improving long-range accuracy. They’re lightweight yet durable, precision-machined (no lapping needed), and equipped with recoil stops and secure locking mechanisms. Made from strong 6061 aluminum, they handle heavy scopes and high-caliber recoil effortlessly. While they lack a QD mount, they provide exceptional value and performance. Highly recommended for a stable and reliable scope platform.Pros:1. Excellent build quality, comparable to premium brands.2. Affordable, costing three times less than similar products.3. Built-in bubble level prevents rifle tilt and improves accuracy.4. Made from durable 6061 aluminum.5. Precision-machined, no lapping required.6. Recoil stop ensures zero alignment under heavy recoil.7. Secure mounting with two Picatinny screws and six locking screws.8. Handles heavy scopes and high-caliber recoil with ease.Cons:1. Lacks a quick-detach (QD) mount.

To begin with I must admit I'm very partial to monstrum rings and optics I personally believe they have some of the best bargains and equipment out there for a fair price I have been more and more interested and active in accuracy target shooting with PCP high pressure air rifles in the 30 caliber plus range I have recently gone from a one inch tube with a 12x24x50 power to a larger one with a 30 mm tube when I found out that monster makes this with an addition to that actually has a bubble level on it I was sold and ordered it immediately anybody who's in to target accuracy shooting will tell you being level is one of the keys to consistent accurate shooting I find that the monstrum works incredibly well for me they all come with the tools necessary to do it meaning Allen keys or torque head screws depending on what you order the attention to quality control and the machining is top notch and rivals even the most expensive ring sets the fact that it also comes with a bubble level is totally cool more so functional so now I'm not guessing if I'm holding the rifles level I'm knowing that the rifle is level it's the perfect size and height and the fact that each ring locks down with not one but two Allen screws two on the bottom of each ring and four on the top of each ring I just can't say enough good about monstrum I feel that they understand the need for quality optics and accessories will not forgetting the average people with average paychecks are looking at these as well they are extremely easy to install and the size was perfect as well the height I could go on and on but how much I like them but I'll end this with anyone who's interested in these in looking for a good rifle scope ring set with a very accurate bubble level securely mounting it to a rifle I highly recommend monstrum Challenger scope rings

These seem nice, but they are absolutely not .80 as stated. Height to center is .85 inches, which is more than 1mm difference - that's all it takes for this not to function in my setup. PLEASE BEWARE, these are 21.59mm and not 20.32mm height to center.

good et of leveled rings

The integrated level bubble is a fantastic feature that ensures my scope is always perfectly level for accurate shooting. The 30 mm size fits my scope perfectly and the 1.26 inch center height provides a comfortable and ergonomic shooting position. The rings are sturdy and durable, holding my scope securely in place even through heavy recoil. Overall, I highly recommend these scope rings to any serious shooter looking for a reliable and high-quality option.