FlexMN dead (?)

After a very long time (2 years+) with my FlexMN, seems both NFC and RFID died.
I tested through Android and Proxmark3.

I’m really sad/disappointed cause I’ve already had a dead FlexNT (in which the low freq tag is still working) and thought this one was not going to fail.

I don’t really now the cause, the last time I used the NFC was around 2 weeks ago, had no trouble or trauma on the implant. I practice mountain biking and kickboxing (using handwraps and gloves) which never caused me issues in the past years, I don’t know if that may be related.
Also, I don’t know if the RFID died at the same time of the NFC, as I use my other RFID implants for daily use.

Any last ideas to check if it’s not only bricked or something?

Commands I used in Proxmark 3: script run hf_mfu_magicwrite -c and lf search
My other implants are working fine, so my Proxmark 3 is good

Out of curiosity, this was the blinky option, LEDs died in around 8 months

What location? Back of the hand with regular handwraps sounds pretty extreme
Do you have a desktop nfc reader?

do hf 14a reader -@ and wave ur pm3 around it where it usually pics up it should start printing out at least something coherently recognisable

Back of the hand.
I use a handwrap like this one + a boxing glove when kickboxing.

I have an ACR122U which I use to log into Windows. I noticed the implant was dead when I tried to log in and the reader had no response

I mean flexes are not meant to flex much despite their name. So 2 years for a big one in that position with lots
of bending seems about right.
My experience is with flexnexts on the back of the hand. They were more fragile though especially the tag itself.

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nothing came up :confused:

also, I started kickboxing 3 months ago, so that may be the issue.
My flexnext on the back of the hand died very quickly, I wasn’t exercising or praticing any sport at the time.
With the FlexMN, I used to mountain bike, lift weights and play guitar, none affected the implant.
So may be kickboxing and having high volume of impact on the implant (even with handwraps and boxing gloves) killed the FlexMN.

I haven’t seen any other case of a FlexMN failing like this, is anyone aware?

I’m sure all of these factors added up over time. A weakness from the manufacturing is also possible :man_shrugging: have you talked to DT about a replacement?
If you get one consider having it on the wrist or forearm. Back of the hand is cool but also risky :sob:

Thanks for the suggestion! Just sent an email through the “Help” button.
I’ll for sure consider other locations

One thing is that the RFID on my FlexNExT (implanted on my other hand, also back of hand) is still working fine (the NFC and LEDs were dead before I implanted the FlexMN). So this made me question even more why only the FlexMN died (both tags). Also considering the fact that my FlexMN was one of the few pieces with LEDs, not sure if that’s something that should be considered

The RFID part is more durable indeed. Maybe there’s a difference between your dominant and non-dominat hand or maybe it’s just inherent from the manufacturing. Is the flexNM on your dominant hand?

FlexMN on the dominant hand and FlexNExT on non-dominant hand, that’s correct.

In kickboxing, I usually punch harder with my dominant hand, but punching should impact the knuckles more than the back of the hand. However, blocked punches are impacting directly the back of the hand.

In general, it makes sense that the dominant hand is more affected, so that may increase the damage

You also make a very tight fist I assume. That bends the flex like a Pringle. Over time that can wear it down.

for sure it does, specially when wearing tight handwraps on top of it.
very tight fist
so it does make sense to wear it down a lot after a couple months of this, 2 or 3 times a week

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Generally speaking, we are no longer making flex implants that use wire core antennas, aside from the flexEM since that is effectively a brick in a biopolymer bag. The problem is that as the flex actually flexes, the enamel in the wire moves over itself and eventually rubs through, shorting the antenna. This is why we are re-working the flexM1 antennas so we can place the COB chips on a flex PCB antenna.

Unfortunately the flexMN is one such wire wound device, so we will not be making it anymore.

@mattsudo … I will reply to your ticket and hopefully we can sort something out with you that you’ll find acceptable.

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