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.
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.
Verdict
Effective and well made, but expensive
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:
General
Bag position Toptube
Mounting type
Bolts, Hook and loop strap
Closing system Zipper
Bag material 600D TPU coated Nylon
Waterproofness
Waterproof
Easy-to-mount/remove Yes
Specifications
Volume (ml) 550
Width (mm) 51
Length (mm) 210
Weight (g) 62
Height (cm) 75
Rate the product for quality:
8/10
Rate the product for performance:
8/10
Rate the product for value:
4/10
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 road.cc?
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.
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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