Is the MK-312 BT modern?


Hi All,

I am delighted to find so much vibrant discussion and so much well thought out documentation re. the MK 312 BT.

I am curious though, the original Erostek 312B is like decades (?) old. Wondering if with modern technology there is an easier and more compact way of doing this? USB chargable LIthium ion battery would seem to be one such change.



Oh, things could certainly be done to upgrade the system. You’re right, the box itself is nearly 2 decades old now. The MK312 was mostly about getting things to parity.

There’s been some work here and there to try and take it further, things like moving to SMCs and what not. Any major upgrades are gonna require quite a bit of work from the electrical, firmware, and software sides though, and I don’t really have capacity to lead that.

There are other “modern” boxes like the Centipede (, but they’re still prohibitively expensive for most users.


Given that the current price of an ET312 is considered steep, I wonder how many customers the Centipede has. Are there any technical facts known about that one?


Thanks for the response! I am very eager to build the MX 312 and will get right to it :slight_smile:

I cant imagine the Centipede having many customers… I have never seen it in any store and the price point is very high. I am also curious to know what it can do that the MX312BT cannot.


The Centipede was developed by a couple of people on the “main” Fetlife estim group. It’s basically an RPi with RS-422 based breakout nodes for different features, including estim, vibration motor driving, etc. It’s “open source” inasmuch as the RPi images are released on the product’s website: Certainly not down to the schematics level though.