125khz RFID Writable rewritable T5577 fob tag for RFID Writer (Pack of 10) (Black)

I've been really impressed with these T5577 rewritable RFID fobs. I picked up the 10-pack to use with a handheld RFID writer, and every single tag has worked flawlessly so far. I’ve used them in a few real-world scenarios: Made a backup fob to keep hidden in my truck just in case I lock myself out or misplace the original. Cloned a pet-sitter fob while I was on vacation so they could access my building without needing to hand over my main one. Copied a pool access fob for my friend group, so we can all get in without having to juggle the original back and forth. Cloning and rewriting have both worked without issue. I've tested re-writability multiple times on the same fob, and it’s held up perfectly each time—no failures, no weird behavior. The chips respond consistently, and I haven’t had a single dud in the pack. Heads-up for first-time users: These come blank, so you must have a compatible 125kHz RFID writer to program them. They won’t scan or read until they’re written to. That’s not a flaw—it’s just how the T5577 chip works. Also, don’t expect these to work with systems like Onity or Proxmark3 RDV4; they’re great for common 125kHz formats like EM4100 and HID. The fobs themselves are durable with a solid keyring hole, and the black color looks clean and low-profile. At under a dollar per fob, this is one of the best values I’ve found for RFID work. Highly recommended for DIY security backups, access sharing, and general RFID cloning projects.

I've tried a couple of brands of writable RFID key fobs and haven't had success. These worked perfectly. My flipper didn't read anything on them when I got them. Perfectly blank. When I wrote to it, it was a perfect copy. I can use my key fob instead of needing to pull my wallet out and take my ID out of my wallet.

You need to write something to the fobs before they do anything. Works perfectly with HID systems and Flipper Zero. The fob comes with a couple small rings, but will go directly on a more sturdy keyring. This is a small fob. On a standard wall sized HID reader, reads at about 2-3cm. On the larger outdoor readers, maybe 6-8cm. Cheap, fast and functional. Zero complaints.

These work great! I hate to say it, but I was pleasantly surprised

I was quite happy with these fobs, they worked great for about 2 months before ceasing. I checked the master tag and it worked fine so I know the signals hadn't changed. Perhaps it had to do with having it too close to another tag or phone or wallet, but I only remember that being a problem in the 1990s. Eitherway, must downvote these as they're not a long term solution.

There good

Work exactly as described. Needed a few extra building fobs so I bought these. I was able to read my key with the flipper and then write to these immediately without issue. These operate at 125kHz, so make sure that is the protocol your device uses or it will not work.

The picture shows 2 tags, which is what I was expecting, so imagine my surprise when I opened the package to find 10 of them. I guess I should pay better attention when I order because it does say "10pcs" in the description. I really only needed one, but now I've got a whole bunch. I wanted to make a copy of my data center access card so I could carry it on the key ring with all my other work keys. That way I wouldn't need to pull the card out of my wallet, I could just use the key ring I would need anyway to unlock the racks. I have to go through several badged doors every time I enter the facility and this fob has worked perfectly every time I've used it. My only complaint is that the smaller rings they come with are REALLY flimsy. One good tug and they'll stretch out. But they come with 2 rings, so it was an easy thing to just toss the crummy one and replace it with the larger, stronger one.

These work perfectly for both 125khz HID & ID cards copying, some other makes don't so it's lucky dip on that front. These are definitely the ones to get 100% recommended! 😎👍

لا يمكن برمجته مع الاقفال الذكية

Funcionaba bien de 10 piezas 8 trabajan, 2 no se pudo grabar.

Fake specifications. Not programmable to 12.5 mhz or 13.2 mhz devices. Probably just a plastic case with nothing inside. Dont buy and waste your time and money

Fue muy fácil grabar la información qu requiero y por si tamaño no es estorboso y lo puedo utilizar en lugar de una tarjeta