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Gravity Nelson Our Staff Review the TROY LEE DESIGNS A3 AS Mips Helmet 2021

This is the first in an occasional series of reviews our staff will be writing. Our shop has always focused on only stocking products our staff use and love, so testing and reviewing products is key to us stocking the best possible products for you.  Check out Wilfred's first review and feel free to chat to him in the store or out on the trails about the amazing Troy Lee Designs A3 helmet (2021). Full review below.

TROY LEE DESIGNS A3 AS Mips (2021) Helmet Review

The Troy Lee Designs (TLD) A3 AS MIPS helmet is a top-of-the-line half shell helmet packed with safety features and customization options. I have been testing this on the trails of Nelson, NZ, which is famous for its long climbs and steep technical descents. As a part time MTB instructor, I was trying to find the safest possible open face helmet to protect me during my time on a MTB, and the TLD A3 fitted the role perfectly. 

In this review I will go through the different components of the helmet, including: comfort, ergonomics, safety, styling, ventilation/temperature, weight, and lastly its value. I will explain my personal experience with the helmet in each component and finally my overall thoughts.

Comfort and Sizing

As soon as I put the A3 on my head, the first thing I noticed was that it felt as though it was giving my head a big warm hug. TLD quote on their website “so comfortable you will never want to take it off” and I will agree with that. There have been multiple occasions where my flatmates have arrived home to find me sitting at the table with my helmet still on my head, even though I finished my ride 45 minutes ago. It felt like your favorite old hat you’ve had for years that seems to meld to your head as if it was made for you. It has great all-round coverage, it is a very deep helmet and it comes down quite far in all directions. It’s one of the few helmets I have tried on where I'm satisfied with the amount of protection on the back of the head and also around the temple. The A3 has a great adjustability and customisation to get the perfect fit, more on this later...

TLD A3 Helmet so comfortable you won't want to take it off


As a reference, I have a head circumference of 56-57cm, and have been testing the size M/L helmet. This means my head is on the small side for the M/L, which is recommended for heads from 57-59cm, however when I tried the size XS/S on, I did not get the same feeling of great coverage and safety as I did from the M/L. If you're bordering between sizes, but your unable to try the different sizes on first, I would suggest going for the larger size. 

TLD A3 Helmet 2021 Size Chart

Ergonomics + Customisation/Features

Perhaps my favourite part of this helmet is its ease of use and all the customisation options. You can tell everything has been well thought out, and works just as it should. 


The helmet features TLDs goggle friendly “3-way Magnajust visor” which clicks into place in three different positions, it is very secure in each position but yet its still easy to move with just one hand. There is an added option of moving the visor past its highest position, which allows full sized goggles or sunglasses to easily fit underneath.

TLD A3 Helmet Fidlock clip

The A3 uses a magnetic 3D-Fidlock buckle which goes together so easily you can almost throw the two sides at each other and the magnet clicks them into place. Once together, it feels extremely secure, and only comes apart by sliding the 2 parts in opposite directions. I highly rate this feature, it's so easy and secure, I don't want to go back to a regular buckle ever again!

TLD A3 2021 Helmet Pads

When you buy the helmet it comes with an extra, thicker, liner and 2 extra “sweat glide” pads. These “sweat glide” pads sit at the front of the helmet and stop the sweat running down your forehead into your eyes. It does this job well, however, it does mean that the sweat gets stuck in the helmet for longer, rather than running out.

A lesser known feature on this helmet is the adjustable height of the rear retention system. Like many helmets, the retention system tightens at the rear with a clicky dial to bring it snug around your head. However, unlike many other helmets, the A3 has adjustable mounting points so the retention system can be moved further up or down the back of your head to create the perfect fit. I have mine set in the middle setting (stock) which fits me great. I have experimented with moving it lower down the back of my head, however, this caused the helmet to be pushed upward when my head was tilted backward as you do when you're standing up, looking down the trail. If you have this problem in the stock setting, try moving the retention system to the high setting, so it moves higher on the back of your head. This will stop the helmet getting pushed upwards by the muscles in your neck.

Troy Lee Designs A3 2021 Helmet adjustabilty


The TLD A3 AS Mips (yes that is the full name) has been designed with safety as a priority. It has a 3 layer shell that includes EPP, EPS foam layering and an outer hard shell. The EPP foam is less dense and is built for low speed impacts. The EPS foam is firmer and is designed for high speed impacts so all your bases are covered. 


On the inside, you will find the “B-Series MIPS rotational brain protection system” which is used to limit rotational forces on the head. This dramatically reduces the chances of a concussion during an impact. 


This Mips liner is linked seamlessly into the retention system, so when you spin the clicky dial to tighten the helmet, it tightens around your head evenly, rather than just tightening from the back. As TLD puts it: “it’s a true 360-degree system”. The TLD A3 received a 5/5 star safety rating in the Virginia Tech helmet testing ratings which is the highest score possible. 


As I said earlier the A3 has great coverage and it sits deeply around your head, providing protection from all angles, giving me the feeling of safety and security I was looking for.

Troy Lee Designs A3 2021 Helmet Safety

Ventilation and Weight

The TLD A3 features 16 ventilation holes, however I still found myself getting a relatively hot head during the climbs. The temperatures I’ve been riding in have not been hot, I've been riding on mild days in a Nelson winter, somewhere around 10 or 12 degrees celsius. Once you build your speed up it gets slightly better, as more air flows through the vents, but I still wouldn't call it “cool”.


The helmet weighs in at roughly 420 grams, which is not light, however it's not excessively heavy either. To compare that with other high end helmets: the POC Kortla Race Mips is 390 grams, Giro Manifest Spherical comes in at 360 grams and Fox Speedframe Pro comes in at 405 grams (all weights are for size medium). My previous hemet was a MET ​​Parabellum which weighed in at just 285 grams and was very well ventilated, so the difference was noticeable for me. However, the Parabellum lacked the safety features that the high end helmets have, and hence comparing their weight would be an unfair comparison. 


I assume the extra material on the TLD A3 is what traps the heat in, but it's also what makes it feel so safe, comfortable, and secure. It's a trade off and ultimately comes down to what you value more. Personally, I don't mind the extra heat and weight, I value the extra safety and comfort it provides. 


The styling on the helmet is great. The colour I have is called Sram white/red, it's the first time I have ridden with a white helmet and I'm really enjoying it, it's visible and I'm easily identifiable. I will admit, I think some of the color options look a bit funny, but that's upto personal preference. The rounded shape with the “shark fin” on the back gives it a unique look and I like it.

Troy Lee Designs 2021 A3 Helmet white


The TLD A3 is not cheap. At $459 NZD it is one of the most expensive open face helmets on the market. While it is more expensive than some of its competitors, there is no denying that it is built to extremely high standards, the levels of comfort and safety technology are class leaders. Buying a good helmet is investing in your future health. Your head and brain are worth protecting. If you have the money, a safe helmet could be one of the best investments you will ever make.

Final Thoughts

In summary, the TLD A3 is a great helmet and I really enjoy wearing it. It is expensive, but the quality makes up for it. The Fidlock buckle and 3-way visor make this helmet very easy to use and adjust on the fly. The deep dished helmet gives full protection and is uber comfortable on your head. The MIPS cradle, combined with the 360 degree retention system, and the 3 layer shell construction provide safety to the highest standard. It has great customisation options with the retention height adjustment, and an extra set of thicker pads to custom fit it to your head. It’s only downside is that it is on the heavy side of the scale, and it is not as well ventilated as some other helmets on the market, but, if safety and comfort are your top priorities, this is a helmet for you.


  • Very comfortable
  • 5 star safety with EPS + EPP foam layering and MIPS technology
  • Great all round head coverage
  • Easy and ergonomic features such as the Fidlock buckle and adjustable visor
  • Comes with multiple padding/customisation options

  • Cons

  • Relatively heavy
  • Quite warm

    About the reviewer:
    Wilfred, or “Wolfie” as he’s known, lives in Nelson, New Zealand and works in the local bike shop called Gravity Nelson as a MTB coach, shuttle driver and shop assistant. Before moving to Nelson he lived on the West Coast for 2 years studying a Diploma in Outdoor Adventure Education.

    Meet wolfie