you should always start small and work up to large plugs.In 2 different sizes!
In 2 different sizes!
A product by well known German dynamo/light manufacturer Busch und Muller. Cracks (oi oi) me up that their website is, to this day, bumm.de.I think these are something to do with dynamos...'Fahrzeugteile' means vehicle parts according to Doogal.
To me though, they will always be Bumm plugs.
What No. fits you?
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