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BBB SealTank Top Tube Bag



Effective and well made, but expensive
Very waterproof
Big enough to get in the way of knees...
...but not big enough for modern phones

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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The BBB SealTank Top Tube Bag is secure and very waterproof, but for such a tiny bag it's very expensive.

For more options, check out our guide to the best bikepacking bags, and our feature on 15 easy ways to carry stuff on your bike.

At just over 0.5L it's just big enough for sunglasses – about the biggest thing you'll fit in here. Put in a multi-tool, a tube, puncture kit and a neck warmer and it's basically full. The sides of the interior are blue for better visibility, but in reality this is just too small to be losing anything in.

2024 BBB SealTank Top Tube Bag 3.jpg

Tools and tubes are arguably better off under your saddle anyway, as while this is small it's still big enough to interfere with pedalling when you stand. The SealTank is best deployed if there are things you seriously need accessible: those sunnies, a neck tube or hat, or energy bars and gels, for instance. Unfortunately you're not going to get a phone in unless you're rocking a Motorola RAZR from the millennium.

With waterproof fabric, welded seams and a waterproof zip, it's entirely weatherproof – great news for those little bits of clothing.

The two long, strong hook-and-loop straps thread through any of five points on the bottom, while the head tube strap can attach either low or high. Snugged up, the bag can still slump a little if you knock it, but it's easily righted. Note the straps are the double-sided type that will attach to your gloves...

There's a hard plastic base inside for rigidity if you choose to bolt this instead, and it (and the attachment loops) are holed already. The bag between them is left unpierced, wisely, in case you don't want bolts. It's easily punched out in the obvious spots.

At £44.99 this is pretty expensive for a tiny bag. The Zefal Z Aero Frame Bag, for instance, is similar but £28.99, and that was judged 'pricey for its size' by our reviewer Stu. Even the handmade 0.8L Restrap Top Tube Bag is cheaper at £39.99.

This does what it's supposed to, then, but that's a pretty niche thing and the price is relatively high.


Effective and well made, but expensive test report

Make and model: BBB SealTank Top Tube Bag

Size tested: 210 x 51 x 75mm

Tell us what the product is for and who it's aimed at. What do the manufacturers say about it?

BBB says: "The SealTank M is our most water-resistant top tube bag, designed for cycling in all weather conditions due to the welded seams and waterproof fabric. The special design makes sure it fits perfectly on top of your top tube, and the three velcro straps keep your SealTank M right in place. The special water-resistant zipper is easy to open and the special blue inner lining makes sure you can find your stuff easily inside without having to take everything out."

Special design, special zipper, special lining... that's a lot of special.

Tell us some more about the technical aspects of the product

From BBB:


Bag position Toptube

Mounting type

Bolts, Hook and loop strap

Closing system Zipper

Bag material 600D TPU coated Nylon



Easy-to-mount/remove Yes


Volume (ml) 550

Width (mm) 51

Length (mm) 210

Weight (g) 62

Height (cm) 75

Rate the product for quality:
Rate the product for performance:
Rate the product for value:

Tell us how the product performed overall when used for its designed purpose

It's a stable and waterproof pocket for a few small things.

Tell us what you particularly liked about the product

Really good waterproofing, secure.

Tell us what you particularly disliked about the product

Too small for a phone, still big enough to get in the way of knees.

How does the price compare to that of similar products in the market, including ones recently tested on

It's expensive.

Did you enjoy using the product? Mostly

Would you consider buying the product? Maybe

Would you recommend the product to a friend? Yes

Use this box to explain your overall score

This works just as it should – it would score higher if it weren't so expensive against the competition.

Overall rating: 6/10

About the tester

Age: 48  Height: 183cm  Weight: 78kg

I usually ride: Vitus Zenium SL VR Disc  My best bike is:

I've been riding for: 10-20 years  I ride: A few times a week  I would class myself as: Experienced

I regularly do the following types of riding: general fitness riding, mtb,

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