Calif. did not issue a letter of compliance for the bullet button. When the law was originally written in 2000, there is a clause in the law that states that if it requires the use of a special tool to remove the magazine, then it is classified as non detachable. The next clause says that a bullet is considered a special tool. In 2001 I met with the reps for the AG. I tried to get a letter of compliance for a receiver that I specifically machined for a bullet button. They would have no part of it, even though the law read differently. I then did the FAB 10 with the fixed mag. They gave me a letter of compliance for that. Whar eventually happened was some attorney donated their time and there were a couple law suits brought against the DOJ. After the DOJ lost a few rounds, they said ok ok ok, will will follow the letter of the law. That is what happened. 2 years ago it looked like maybe the bullet button was going bye bye. Surprisingly our Gov. did not sign it. The NY10 was going to be the CA 10. I developed it just in case. Since I was already half way thru the patent process, I finished it just in case for the future. They will never give up. Calif made it very clear that they will never issue another letter of compliance again. I am one of only 2 ever issued. From that stand point, Calif is no better off than NY. The one thing I do no for a fact is that ATF considers a permanent alteration as one that requires drilling, grinding or machining in order to reverse the alteration. It can not be just the simple use of tools. The NY10 requires drilling, grinding or machining to remove the mag, unless you chain it to your bumpers and rip it a part. Having been down this road before, I have tried to be as thorough as I can. I still have someone in NY working on getting it to the AG's office.Believe me, I do not want anyone having to share a cell with BUBBA. Craig