Any worth of equity of a private company

I got an offer from a private company, Sophos, where the equity is about 250K. The recruiter said, they will give 6500 units. This company is not public yet and I don't know if it will go public in near future. My question is that whether there is any value of this equity if the company doesn't go public and I plan to quit before that. The recruiter also mentioned that if I plan to leave, I can sell my equity back to the finding company Thoma Bravo. I do not know how does the buyback work if at all it works. Any thoughts? #offer #sophos #engineering #software #swe