First time back on 2k in 9 years.

Always loved the game but just had so much shit to do over the years that I never had time to play it so I stopped buying it. Recently just got so much more free time on my hands that I got the game and made a my player and been playing for a month now and I’m a 93. One thing I don’t get is the cap breakers. What is it and how do I get them ? Someone online told me that I need the cap breakers for my 3s and I was like “yeah” but had no idea wtf he was talking about