Sea slug?

[Gianluca]

Hi everyone. So I was looking in my QT tank and I noticed this little guy. They look like sea slug that also looks like a rock lol. I want to know if they’re reef safe so I can transfer them over to my main tank
See pictures posted for a better description
Let me know if better pictures are needed

 

[Brit’s Fish]

Looks like a Stomatella snail to me! I love those guys! They’re very reef safe & if you have more than one, they’ll reproduce well in your tank.