I have AVID chips in all of my snakes except one and have had them there for almost 2 years (a year and a half before required by law) and haven't seen any adverse effects as of yet. (knock wood) All of my were placed by ACS officers during a pet drive they have every year.I haven't had to use mine yet either, but hopefully if I ever do need them they will do their job.
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0.1.0 Burmese Python 12'
1.0.0 Burmese Python 5.5'
1.0.0 Granite Burmese Python 5.5'
1.0.0 Burmese Python 10.5'
1.0.0 Reticulated Python 7.5'
1.0.0 BCI 7.5'
0.1.0 BCI 5'
1.1.0 Bearded Dragons