Usually the boxes of screws come with the bottom, more silver bit. But today’s box had the duller grey, bit with a green lap band. No idea if one is better than the other or not.
Edit: Thanks to @0x0@infosec.pub for the wiki article!
Bits like that are used for impact drivers
It’s green because it’s not quite ripe yet. Leave it in the sun for a few days, and it’ll be good to go.
Seriously. Trying to chew that thing before it’s time and you’re gonna lose teeth.
Alternatively you can chew it when your time has come to speed things up.