Bells and whistles (idiom)
When something has bells and whistles on it, it means that it has lots of cool features.
Think about your smartphone and just how many features it has, there are so many that you may not even use and perhaps you don’t need. Even so, companies still continue adding capabilities and extra features which they say make our lives easier.
You can also describe items like cars as having all the bells and whistles.
Hit the Nail On the Head [Idioms] - MyEnglishTeacher.eu
Take a look below:
Alan: Nice car, Francis!
Francis: Thanks Al, I bought it last week and I’m really enjoying it!Alan: It looks cool, how much was it?
Francis: It cost a lot of money, 30,000 pounds, but it has all the bells and whistles as well!
Alan: Oh wow, what does it have?
Francis: Well, with this model I get in-car wifi, heated seats and a satellite radio.
So, as you can see with Francis’ fancy car, to have all the bells and whistles can be a good thing but it may also cost a lot of extra money!