A bluebottle is a species of flying insect, the "common blowfly", which has a metallic-blue body (Oxford English Dictionary).
As a fly, bluebottles are extremely annoying and persistent. The integral Anti-Burglar Buzzer is likely to be loud, annoying and persistent as well.
Lexicon list of Broom Manufacturers
From the Web
WizardingWorld.com (Pottermore) features:
Harry Potter Wiki: Brooms