So I purchased the bundle here:
I assumed it was just one chip but there’s two implants. What do I do here? is the xEM or the xSIID better to implant? Should I implant them both? Which is more versatile? I’m very new to this field, and I really need some advice about these different chips. I’m quite confused.
Welcome!
The NeXT Implant contains both T5577 and the ISO14443A NFC Chip. (But without the blinky light).
That’s up to you 
. All depends on your use cases.
Do you have an idea of what you wish to do with your implant(s)?
Yes, more chips is more better lol
Real answer, the XSIID will cover the HF 13.56 side of things and the Xem will cover the LF 125khz side of things
One isnt better per se… just gives your more possibilities and coverage
It’s always best to start with your intended use, but let’s break that bundle into two halves to see if that makes it easier.
The low frequency portion is the xEM implant, and the xAC controller. These are useful together if you want to open something that you have built / control. This is a good example of what you could do, also useful for homemade house door locks.
The high frequency portion is the xSIID, and the keyboard reader. These are useful together for electronic logins on PCs and such. An example is HERE.
You can also clone the xEM to duplicate some older style (but still in use everywhere) RFID key cards. Think work badges and such.
That should be enough to get you started. If you come up with something specific that you want to do with your implants, then let us know and we’ll all try to get you headed down the right path. There’s some wicked smart people floating around here, and they’re all pretty helpful if they can be.