AP20 Trunk Top Bag


Size: 20L

The AP20 Trunk Top Bag is a 20L roll-top bag that attaches to any Carbon or Alloy Rack in a matter of seconds.



Top Bags

AeroPack Trunk




20 litres



Bag Dimensions

435mm Long x 165mm Wide (Rear) / 130mm Wide (Front) x 400mm High

Seam Type

High Frequency Welded

Fabric Material

Nylon & Hypalon Laminate

Max Weight

9kg / 20lbs

Max Laptop Size


Fitting Time

10 seconds or less

*These weights do not include the removable stacking straps (50g) or the removable bag backbone cover (40g)

Media Reviews

Top tip: Try searching for your bike make/model below to find others using this product on your bike.

Customer Reviews

Based on 65 reviews
Diane Humphrey (AU)
Bike: Giant Devote
Riding Style: Road / Ultra-endurance
Waiting for spacers!

Haven’t been able to try my Tailfin out yet because spacers were missing and I am still waiting for them to arrive.😳

Hi Diane, thanks for leaving us a review. Sorry for the delay with this, I can see the courier is taking their time delivering the part to you so I’ve sent an email to you as we’ll get this fixed ASAP. All the best, Dan

Yuriy Kulikov (DE)
Bike: Specialized Fuse
Riding Style: Bikepacking
Very well engineered and worth every penny

Tailfin Aeropack is one of the best pieces of equipment I have ever bought for bikepacking! Main advantage is the packing speed and convenience compared to regular seat bags and better aerodynamics compared to panniers. Packing speed makes a huge impact and I would certainly recommend this bag for every backpacker.

Before I go into details, i use it on a Specialized Fuse hardtail with Tubus Disco carrier, mostly for bikepacking. I have a small handlebar bag and a small frame bag. Most of my stuff is in the Aeropack.

The pack fits perfectly behind the seat and has about 15 liters of storage (it can be less and up to 20, but 20 is quite bulky. It is very stiff (no sway whatsoever). It fits my sleeping bag, cooking system, food, clothes, glasses and some small stuff.
It is easy to take it off thanks to the quick release system which is simply ingenios. You can take the bag with you when on a break of take it in the tent. I am using a Tubus carrier, but Tailfin carrier would work just as well, if you have an extension to move the Aeropack backwards a bit. I don't think the Aeropack with integrated stays would be as convenient as a standalone bag though.

Access is from the top (rolltop) or from the side (zipper). There is a small pocket which I have used for small stuff which I need seldom.

Water doesn't get in, no worries here.

One change I would with for is a slightly longer side zipper, because sometimes it is hard to get the stuff out this way. Another would be detachable net on top to out wet clothes to dry.

Kea (IL)
Bike: Trek 520; Fuji Gran Fondo; Trek Checkpoint
Riding Style: Bikepacking, Commuting
Excellent product - needs a few tweaks

The AP20 is a great pack and Tailfin is an outstanding company. I’ve used the AP20 for a daily (3-5 times/week) 9-mile each way commute for the last five months and have been extremely pleased. The pack is a high-quality build and has many great features. It also has a few shortcomings that stop it from being a 5-star product. Tailfin is a 5-star company and great to do business with. I look forward to future products and will continue to wish them the best.

In terms of production quality, the bag appears to be solidly made. It is waterproof and seems relatively sturdy. I have not had any experiences that would really test its durability though. Clearly, it doesn’t rip easily. You don’t need to be particularly gentle with it.

There really is a lot of space in the pack. The AP20 easily fits all my stuff for the daily commute with plenty of room to spare. Because it has a roll-top, it will compress down to the smallest size possible depending on how much stuff you’ve put in the bag.

The pack attaches nicely to the Tailfin rack and you almost don’t know it is. It doesn’t wobble or anything. It really does attach in just a few seconds. The geometry of the setup requires the front to be shorter than the back, so angling the pack onto my bike isn’t always as easy as I would like. It also is a little limiting when you are packing the bag because you end up putting less stuff up front so that the bag can easily attach to the bike.

The AP20 has a zipper that lets you access the inside of the pack without opening the whole thing – a clever feature. The other side of the pack has a small zippered pocket. Like the bag, it is somewhat angled with the front being slightly shorter than the back. However, in my opinion that whole pocket is too short – it should be about 2cm or 3cm taller so that it can accommodate a cellular phone. That would make it more useful.

When you have the pack on your bike you can’t have a wedge pack to keep all your repair equipment in. I usually just pull it off and drop the wedge into the AP20. If Tailfin had a small flat pack/case of some sort that can hold a repair kit that might be a nice additional accessory. You could put your repair stuff in there and drop it into the pack. It could fit into a zippered pocket or accessible from the main pocket zipper.

I gave the AP20 a 4-star rating. There are a few features that hold the AP20 back from a full 5-stars, although I think it is a great product.

The AP20 has a pair of straps that go over the top to cinch it down and make it nice and compressed. The straps even have connectors on them so that the loose ends are not flopping around the back of your bike. The problem with the straps is related to the bag design. The geometry of the bag means the front is slightly shorter than the back and you end up packing less stuff in the front so that it can latch into the bike rack. Sometimes this means the front strap doesn’t stay on the bag and slips down the shorter end. You can mitigate this by crossing the straps, but the straps aren’t long enough to do that if the bag is more than half full. Having longer straps or something to stop them from slipping would be helpful.

The roll-top feature, which is great for both access and compression has one drawback. It relates to adding a light to the back of the pack. Specifically, there are notches on either side of the strap connectors so you can attach two rear lights on either side. Tailfin sells an accessory that mimics a seat post. You can screw it onto the base of the AP20 and attach a light that way. Making that standard would be a good idea since I think most people only want one light.

The AP20 can’t be beat as a great pack on the back of your bike. It does have a couple shortcomings when it comes off the bike though. It is awkward to carry all by itself as there are no handles on it. The pack has loops on either end of the roll-top connectors so that you could attach a shoulder strap. Tailfin does not include a shoulder strap with the AP20 and does not sell one separately (although one does come with the 22L panniers). The other issue is that the pack just doesn’t seem to sit right when you set it down. The bracket on the back is designed to fit onto the Tailfin Bike Rack, not to sit on a table or bench. In fact, I worry that it will scratch a nice surface. Putting larger “feet” with rubberized bottoms under the attachment springs might help. Alternately, making the Light Seat Post Mimic more substantial with a rubberized bottom might do the trick.

The pack is a bit on the pricey side. That's just a fact. Having said that, it comes from a small company and isn't really from a mass-produced conglomerate - so those people have to get paid somehow. As mentioned, there are a couple things (seat post mimic for light and shoulder strap) that I would like to see included as standard. I’m quite pleased with this product and look forward to purchasing future Tailfin pr...