off-road.cc

The Lifeline Adventure frame bag fits 2.1 litres of storage beneath the top tube. It's a simple design with a single zip and one large storage area, while its 300D ripstop nylon fabric and welded seams mean it's both light and impressively waterproof. It might not be a looker, but it's cheap, simple and effective.

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The broad Velcro straps prove easy to use, and secure with no decrease in strength after multiple uses. They're long enough to fit around all bikes, from skinny steel tubing to wide carbon frames, though as they're unadjustable they may interfere with your cablestops. At 155g all up, it's light too.

The design is simple: a single waterproof zip opens on a single storage area. The zip copes well and stays smooth even with the bag bulging and needing some force to close it, and when closed it sits in a small zip garage, which stops it from rattling around.

There's a small cable access port near the front, which is handy when storing headlight batteries remotely or charging things while they're on your bars. The waterproofing is impressively unaffected by this hole, as in extremely heavy rain and even exaggerated testing with a hose pipe, the Lifeline Adventure stays completely dry inside.

At 2.1 litres it isn't the largest of frame bags, but the simple design and slim, light fabric means you can make the most of the space available. The shape makes the most of frame designs with a triangular front section, and should leave bottles accessible on most bikes.

Fitted to a 54cm road/gravel bike, for instance, it left enough room for two 750ml bottles in standard (not side access) cages. Yes, it can bulge further than the claimed width of 5.5cm when full, but not so much it interferes when pedalling.

At £19.99, it's very easy to overlook the plain styling and lack of internal dividers and just enjoy the benefits. It's £15 cheaper than the small Passport Frame Bag that reviewed well previously, and in a different bracket entirely from the likes of Bontrager's Adventure Frame Bag at £69.99 (we tested the £80 three-litre version here).

The Lifeline Adventure is a budget friendly and well-designed bag that's simple yet performs very well. The quality is good, the waterproofing is impressive and it doesn't actually give away much to more expensive competition – it's basic, but absolutely does the job.

• www.hotlines-uk.com

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