ROCKBROS 840D Nylon Bike Triangle Bag (3L) Review
This is a small wedge bag rather than a frame filler. It holds tools, spares and snacks under the top tube, and on most frames leaves room for bottles below.
The verdictA cheap, light wedge that keeps the bottles in play on most frames. Expect the zips to be the first thing to go.
The listing gives the 3 litre version as 40.5 cm long, 12.5 cm deep and 6 cm wide, at 198 g. It is a wedge that hangs under the top tube rather than a bag that fills the triangle, held by five hook-and-loop straps with 11 mounting holes to choose from. A rigid plate keeps its shape, and there is a zipped compartment on each side.
That shape is the reason to choose it. On a medium or large frame the bottle cages usually stay in use, and one owner keeps two bottles on a 58 cm frame. ROCKBROS itself warns that it can foul bottle cages on some frames, so measure the space under the top tube before ordering, and look at the 4 litre version on the same listing if there is room.
The fabric is heat-pressed 840D nylon, and ROCKBROS claims it keeps out 95 percent of water. Owner reports on water split almost evenly in Amazon's review summary, with one owner finding water pooling inside, so treat it as shower-resistant and bag anything that must stay dry. Hook-and-loop straps can mark paint, so protect the contact points.
Zips are the weak point in the owner record. Amazon's summary counted 28 negative zip mentions out of 37, and owners describe failures after six months, 16 months and about two years. Owners on Amazon US gave it 4.5 stars from 1,705 ratings in October, with about 3 percent at one or two stars.
What works
- 198 g and leaves room for bottles on most frames
- A compartment on each side
- 11 strap positions for different tubes
What doesn't
- Zips are the common failure
- Water resistance is a claim, and reports are split
- Only 3 L, not a frame filler
Buy it if
Riders who want tools, spares and snacks in the frame while keeping their bottle cages
Skip it if
You need to fill the whole triangle, want electronics kept dry without a pouch, or ride a small frame where any wedge blocks the bottles
Others we scored in this category
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