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.

Needed additional fobs for our condo and didn't want to spend $50/ea for two more. My son's friend had a copier and it worked perfectly.

Works perfect with flipper zero.

If you're looking for a re-writable T5577 rfid fob these are a great value. These however DO NOT work with the Keysy rfid duplicator. Keysy only works with specific rfid fobs and this is not one of them. I was able to duplicate through a flipper zero however so if you find a generic duplicator other than Keysy that works with T5577 it should work.

Software is malware. It's blocked by every virus app. Do not buy.

I had a batch of these that weren't working with the Proxmark3 RDV4, gave up and ordered from another vendor. Then I ran out of the other ones and they were discontinued, so i looked at these again. Turns out Kyle D's review is right on. Play around with positioning for programming and then reading for verification until it works. They read fine once you can get them programmed successfully.

all of them work and are very durable, pretty small as well and super easy to use.

Copied my apartments access card to this key fob and it works perfectly, thanks!