From Townhall.com:

Until now, gun control laws hadn’t mandated the confiscation of weapons; generally, banned guns were grandfathered in under previous laws so their current owners could continue to legally own them. The Connecticut law changes all that. Passed last year in response to the Sandy Hook shooting, SB 1160 bans so-called “assault weapons” – certain rifles, more recently known as AR-15s, that have been singled out based on purely cosmetic criteria – and magazines that hold more than 10 rounds of ammunition.