Over the years we have extensively reviewed bumper cases machined out of aluminum, more than most blogs could brag about. So we know a thing or two about what makes a winning iPhone bumper case that is made out of a premium metal. If there is one thing that matters when it comes to aluminum cases it's design. Looks are the most important features when protection is thought of as a side dish. This isn't your $20 -$30 plastic case you'd purchase depending on the level of protection you're looking for.

Designed By M recently went up on Kickstarter with its version of what a minimalist aluminum bumper should be like, and as a result the AL13 aluminum iPhone 5 bumper case was a proven as a successful proof of concept people were willing to spend $80 on. We've been putting the AL13 thru our usual thorough testing just for you. So be sure to read our full review after the jump!

Designed By M's AL13 is a super simple, lightweight, screw-less machined aluminum iPhone 5 bumper case that is being offered in slate black, gun metal, silver, blue and red anodized colors for $80. An iPone 4/S version is also available. Normally we find little interest in showing the packaging of a case, however, this one is made using the same type of metal as the product that it cradles inside. Designed By M could have slapped a traditional cardboard or plastic packaging around the AL13, but instead the company opted to create a matching aluminum container with a sliding lid for living up to the premium qualities of its $80 aluminum bumper case.

The AL13 sits protected inside a foam insert where it is contained inside what seems like more aluminum than the amount used to create the bumper itself. Insane, but gratifying too. A nicely packed set of screen and full back protectors are also included, which is great being that this is a bumper-style case with a full opening around the back. Not surprising though, the screen plus back protection kit is made by Incipio and isn't of any particular high quality. We recommend using tempered glass screen protectors if you want flawless touchscreen experience.

Diving straight into what matters most, the AL13's interior is brilliantly lined with a thin layer of a dense foam material to prevent any scuffing and metal-on-metal contact. And when I said brilliantly, Design By M made sure to cover the entire interior with this stuff unlike many aluminum bumper cases that lack such essential protective layering.

Although we have reviewed screw-less aluminum bumper cases in the past, the AL13 is actually the first to features a screw-less installation with a sliding closure implemented into the design. And let me tell you, it's the easiest and quickest to install/remove screw-less aluminum bumper we've tested by a land slide. Insert your iPhone 5 into the bumper front side down, and then slide what Design By M calls the Simple Slide Cover which is the back frame portion of the AL13 that slides into the back of the bumper until it securely snaps into place.

To remove the Simple Slide Cover frame, you would need to lift up one of the two corners which have a notch for your finger nails to lift out of the locking position. Again, it's much easier and painless than it sounds. Speaking of the notch area, the edges at the bottom of the Simple Slide Cover frame are a bit sharp and have an unfinished surface like they should have to match the rest of the edges all around the bumper itself. You notice the bottom edges in your palm every once in a while, unfortunately it's a small refinement caveat left in the open that should be pointed out if perfection if all you care about.

There is a tiny bit of play between the sliding frame and the bumper itself which seems like a thickness miscalculation rather than the interior foam having anything to do with how snug the fit is. Because the fit is snug width wise, but not in terms of thickness.

But, Designed By M has taken into account one important aspect and that's compatibility with protective back as well as front films. There's just enough play between the sliding frame in order to accommodate virtually any type of protective back film which enables you to slide the frame into place without causing any issues. After applying the full protective back film, I used a Spigen kit which I prefer better than the one included with the AL13, the Simple Slide Cover fit much better with very little room left for it to move. I wouldn't say the fit is as good as it should be, but it's really close as long as you put on that included full back protection film. Otherwise, you'll be disappointed.

I would recommend using the back protection film for three reasons: protection against scratches even though the bumper itself provides adequate lay-on-the-table edge around the iPhone 5, to avoid any play between the parts as well as to avoid potentially causing scuffs when installing and removing the Simple Slide Cover frame as it does overlay that back of the iPhone when inserted into the bumper. 

AL13's highly minimalist design is mundane, yet somehow it profoundly pleases you aesthetically

AL13's highly minimalist design is mundane, yet somehow it profoundly pleases you aesthetically when you stare straight at your iPhone 5's screen or when you set it on the table at an eyes distance. It looks good from any angle, especially from the front, which is a place where most cases have nothing to add. The AL13's pin-stripe-esque profile makes it seem like it trims the periphery of the iPhone 5 with a really attractive semi-polished metal edge that is totally pleasing to have around.

That minimalist profile of an edge contributes little to bulk, and a lot more to the unique characteristics of using a machined aluminum bumper. The difference in how the AL13 is designed in terms of simplicity is subtle, but noticeable compared to many other bumpers of this type and that is what helped make it a success on Kickstarter.

If I would admit, my initial impression of the AL13 was that it looked mundane and not impressive having used the Draco 5 and the Sector 5 among many more complex aluminum cases. Looking at the AL13 now, sitting there whilst its bright red metallic pureness envelops my black iPhone 5 - I find myself more attracted to its flat chamfered design and top notch quality finish.

The smooth anodized finish is refined, and while the AL13 only comes in a semi-polished finish, the polish is subtle to the point where you can still notice the machined aluminum texture beneath if you look close. The red color we have here happens to change its shade beautifully under light, from deep vibrant red to an almost hot pink depending on the angle. The polish gives the color a beautiful lustering shade that pops to grab your attention like a delicious candy apple. While not identical to the iPhone 5, the AL13's edges are chamfered to reflect and shine around light brilliantly. The effect reminds me why these often expensive aluminum cases are even in existence where plastic simply cannot replicate these premium qualities of metal.

There is more to like with the AL13 like its bottomless port opening which lets you use Apple's various Lightning adapters. Although the opening is nice and wide, the AL13 isn't going to fit most speaker and charging docks except for the ones with a pointy Lightning connector designed specifically to fit such protective cases with a recessed Lightning port opening.

Comparing the AL13 against the equally priced T-type 3 by 4th Design aluminum bumper - you can see how significant the coverage is around the back where the AL13's Simple Slide Cover overlays the back of the iPhone 5, whereas the T-type 3's plastic frame closure it much narrow and only covering very little area. It comes down to personal preference, but I think Designed By M should have narrowed the frame down slightly to cover less around the back of the iPhone 5 as it gives the AL13 is constraining appearance that I'm not a big fan of.

One thing to note is that while the T-type 3 is a very slim minimalist bumper, it has an ugly scar on its right side in the form of a SIM card slot which breaks the seamless nature of its smooth and elegant style. Whereas the AL13 boasts a much cleaner body that people might like better, and that's really one big factor that makes the AL13 a truly minimalist aluminum bumper.

However, by comparison the AL13 is noticeably thicker than the T-type 3 and you notice that when holding it in hand. Its wide flat shape isn't as comfortable to hold as the more petit T-type 3, but then again it also isn't the worst aluminum bumper I've used and I quite like using it after the fact. Just not enough to persuade me from removing it and locking into the T-type 3 when I'm in the mood for some metal protection affection.

Little attention to detail went into the AL13 despite having managed to grab many people's attention, and I'm saying that because compared to the T-Type 3, the AL13 has no integrated buttons to fit the seamless design but instead ordinary cutouts which if I'm honest, aren't very pleasing to press a button thru.

Of course there's the never-ending cycle of signal loss concerns when anything metal is at play. Being that the AL13 is entirely made using an all-aluminum construction, it affects signal reception, albeit the impact is minimal compared to other cases. At most you'll notice a drop in one bar which we think is acceptable. No issues with GPS location and tracking. Nor is there any data speed degradation with the AL13 bumper installed.

All in all, the AL13 is a beautifully simplistic metal bumper with smooth industrial goodness and effortless on/off installation method. And for that it should be looked at, a minimalist bumper designed to accentuate the iPhone 5 with its flat streamlined styling and chamfered edges that glisten premiumness at your face. There is a but however. As with all all-aluminum bumper cases you should consider a drop in signal reception, the AL13 is not for you if you constantly get a bad signal. Moreover, at $80 the AL13 isn't offering you a whole lot of bang for your buck except for slick looks and a quality finish. Which you could also get with 4th Design's T-type 3 - and at a slightly improved feature experience too.

The AL13 isn't perfect, it doesn't have a bang on precise fit between moving parts nor did Designed By M pay much attention to the smallest of details. We don't like the fact that in order to achieve an overall good fit, one must install the included protective back film or else parts have play in them. And for that reason, the AL13 is too basic to be too expensive at this point for us to give it our general recommendation. Hopefully this will get sorted out soon, and if so we will try to update.

Thinkbym.com