A bell should cost little and fit the first time. The Accmor manages both, and it says exactly which bar size it fits.
What the listing publishes
Aluminum and engineering plastic, a fit for bar tubes of 0.83 to 0.86 in, one screw, a minute’s installation, a weight of 0.04 kg, and more than 35,000 ratings.
Where it goes
0.83 to 0.86 inches is the common 22 mm grip section of a flat bar. On a drop bar or the wider center of a mountain bar, it will not fit. Put it close to your thumb, inside the grip. A bell you cannot reach without moving your hand from the brake goes unused.
What to check before you buy
Measure the section of bar where you plan to fit it. Then check for space beside your shifter and brake lever, because modern controls fill that area quickly.
What we rate and what we flag
Strengths
The clearest bar size on this shelf
More than 35,000 ratings
Under $6
Compromises
Fits 22 mm bars only
No sound level is published
Small dome
Specifications
Material
Aluminum and engineering plastic
Bar size
0.83 to 0.86 in (22 mm)
Size
2.1 × 2.1 × 2.3 in
Weight
0.04 kg (1.4 oz)
Fitting
One screw
Model
AC8076
The questions riders ask
Will it fit near the stem?
Only on a 22 mm section. The bar center of many bikes is 31.8 mm, so fit the bell out by the grip.
How is it fitted?
One screw, around a minute of work.
Our score
7.5/ 10
Cheap, clear about fit, and hard to fault.
Against the closest bike gear on price
Same category, nearby prices, between bike gear. What remains is the specifications every one publishes — half empty, a column is no use.
Specifications: the manufacturer sheet for bike gear and the matching Amazon product page. Prices and availability: Keepa. Every figure on this page names its source.