low filament sensor

Hey guys my name is Justin, and I am an inventor and 3d printing enthusiast. I just finished testing my low filament detector for 3d printers. When your filament runs low it will sound the alarm giving you time to pause or reload your filament. This item is very simple but also very reliable, when your half way through a five hours print and your printer runs out of filament, this will save the day. It will also save you money by letting you use that last little bit of filament left on each roll.
Each unit comes with 5 tops so you can pick the color that matches your printer.
It will work with 1.75 or 3mm filament, by changing a part that is included.
I have it listed on my website eBay and amazon if you want to get it on my website use promo code reedswitch for 10% off.
My website


Check out the videos.


About $35 shipped seems a bit steep, otherwise nice work!

right now it is $25 USD Free USA shipping use promo code reed switch for 10% off

price may change in the future.

not open source?