Stromerbikes are factory-fitted without a bell but with a horn. This is the subject of controversial debate. Some find it too loud, others too quiet and still others don't like 'the sound'. In older models, it also suffered under the influence of splash water from the front wheel and sometimes failed to work.
The classic bicycle bell is a good alternative. There is a huge range on offer - but with huge differences in quality.
The velojournal.ch tested 18 bells and also provided an audio sample. Here to the article.
A few examples of good bells:
KNOG Oi "Luxe"
KNOG Oi "Classic"
SPURCYCLE "Bell Raw"
NEVER2FAR "Bar End Bell Road & Gravel"
This bell fits into the end of the handlebars of the ST7, for example, as standard mounting is hardly possible due to the thickness of the handlebars.
BBB "Loud & Clear Deluxe BBB 15" (cheap and good!)
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