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This neat BTR Waterproof Under the Bike Saddle Wedge Style Bike Bag offers brilliant resistance to the outside elements at a great price, plus it'll carry plenty of kit too.
Riding around five or six different bikes a week over all sorts of disciplines, I'm a fan of the humble saddle bag as it easily allows me to swap my tools and spares from one steed to the next in a matter of seconds.
The BTR uses a seatpost strap and two bits of fabric that loop over the saddle rails before clamping to the side of the bag, so attachment is simplicity itself.
A complete lack of zips is something I like, especially on a bag that is going to be used year-round on a bike without mudguards. There is nothing to rust or get full of dirt when covered in road spray.
To close the BTR you roll the end down and then clip it to the main body of the bag and this, alongside the waterproof material, keeps the water out and your tools and kit safe and dry.
I rode with the BTR in some properly horrible conditions, with its toughest test coming by way of a three-hour ride in very heavy rain. The deluge had already been going for about five hours so there was floodwater everywhere being sprayed up onto the bag. Not a single drop of rain got through.
The main compartment of the bag has a reinforced base to maintain its shape and when the rear end is folded up it still leaves you with a pretty decent space of 9cm (width), 8cm (height) and a length of 18.5cm.
I could easily get a couple of tubes in there, CO2 canisters, multi-tool, tyre levers and puncture kit with room to spare, so you could even pack in some gels and stuff for longer rides.
The adjustable straps allow you to cinch in the sides of the bag to keep the contents in place when it isn't full and also mean that you can narrow it to make sure it doesn't clash with your thighs when riding.
Other neat little touches like the rear light loop are handy because, if you run only a short amount of seatpost then the BTR will restrict fitting a light directly to your bike.
There are also reflective details, too, on both the sides and the rear.
Price-wise, £14.99 is pretty impressive indeed. Blackburn's Grid Small Seat Bag is much smaller and costs a fiver more, for instance.
The Fabric Contain Large Saddle Bag offers similar sizing but it isn't waterproof. It'll cost you double, too, at £29.99.
For a simple solution to carrying your tools and kit whatever the weather, you can't really fault the BTR, especially for the money.
Durable and easy-to-use saddle bag that'll keep your ride essentials dry
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road.cc test report
Make and model: BTR Waterproof Under The Bike Saddle Wedge Style Bike Bag
Size tested: Width 9cm, Height 8cm, Length 18.5cm (when rolled shut)
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
BTR says, "From the BTR All Weather Bike Bag range that are based on hiking dry bags, this is a mini version that attaches under your bike seat, so you can keep your belongings safe & dry & you can focus on your ride.
"Under saddle bike bags generally get a raw deal from cyclists as they get splattered with mud & dirt. The all-weather bag by BTR bag folds down & clips together to create a dry & dirt-free area so your belongings stay dry & clean!
"Our universal fit BTR All Weather Saddle Wedge Dry Bag is designed to keep your valuables secure & dry in all weather conditions.
"Built in rear tail light loop so you can use this & your bike light so your bicycle remains visible
"We also added plain reflective stripes on the side, so you have a practical added reflect & no excessive branding."
The BTR is a simple and effective waterproof bag that carries all of your essentials.
Tell us some more about the technical aspects of the product?
100% waterproof material - your contents stay dry
Roll down & easy clip waterproof bag fastenings - no zips or fastenings to let the water seep in - keeps your contents dry lets you access inside it fast!
Rear light loop– clip your red rear light on the built in loop. No need to compromise visibility for storage!
Universal fit - Adjustable straps ensure it attaches whatever the diameter of your seat stem & it stays put - does not move, shift or budge easily!
3x Fastening straps - 1 x hook & loop that secures around your seat stem, 2 clips attach & adjust under your bike seat for maximum stability
Re-enforced base - our bag won't sag or get misshapen & catch on your bike wheels. Designed to retain its shape
Reflective stripes - on the side & reflective logo on the back – reflects headlights back to the source & so helps you to be seen & be safe!
Wipe clean material – easy to keep it looking good!
All weather bag – not only keep the rain out but the dust & dirt out too!
Width 9cm, Height 8cm, Length 18.5cm (when rolled shut)
Tell us how the product performed overall when used for its designed purpose
Remained secure on the bike and keeps the rain out.
Tell us what you particularly liked about the product
Tell us what you particularly disliked about the product
Nothing really to dislike.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
Considering its size and waterproofing, it is priced very well against the opposition.
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
A simple bag that holds pretty much everything you'll need for a day ride or commute, and it's waterproof too.
About the tester
I usually ride: This month's test bike My best bike is: B'Twin Ultra CF draped in the latest bling test components
I've been riding for: Over 20 years I ride: Every day I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed
With 20 years of road cycling and over 150,000 miles in his legs it's safe to say Stu is happiest when on the bike whatever the weather. Since writing his first review for road.cc back in 2009 he has also had a career in engineering including 3D-CAD design and product development, so has a real passion for all of the latest technology coming through in the industry but is also a sucker for a classic steel frame, skinny tyres, rim brakes and a damn good paintjob.
His fascination with gravel bikes is getting out of control too!