Yes PM model réducteur 5:1.
I do not hide you to have tested my kill switch on the test bench (propulsion in a pool) because the after-sales service of Heifi had told me that the kill switch was not dangerous for the esc … it is true that the esc always works after many tests …
But I am not very serene either during my first tests after the deconfinement…
Note that the 300 pro plus has its own failsafe in case of a 100ms loss of connection the esc cuts out, isn’t that enough protection?
Got it, sounds cool. I’m thinking about doing some bath tub tests here in the dorms! I am unsure how robust the 200A VESC I have from Flipsky is so I am going to treat it nicely. 
Yes someone pointed out these settings are in the VESC as well! I’m going to use them and leave my PPM signal input floating when the safety leash magnet is not present. The loss of connection timer is a great feature.
I do it like you said 
How to add a magnetic switch to your efoil electric surfboard: found on the Michobby site
The magnetic switch can be connected to the 5V cable of the signal cables. When the switch is turned on, the receiver continues to output signals to the ESC. When the switch falls off, the receiver stops outputting signals to the ESC, then electric surfboard or efoil stops working.
On/OFF powering of the receiver with a magnetic switch: should we totally abandon this idea, even if a waist leash seems to be a good answer to @PowerGlider questions:
How does your 12S12P VTC6 perform? I’ve just finished building one too (for my jet board)
That is to say … I performed his first charge without any problem after setting up the BMS. To date I have not yet tested the board in autonomous mode. I still have one or two things to do before a new vacuum leak test before a test with an on-board battery.
Nice. I still need to build my board (2nd one). Again… It is a jet board!
However. Like you fly guys boards… The jet board needs to be watertight too… This is for me the hardest part of the builds
https://flipsky.net/products/antispark-switch-pro-280a?variant=9104991682620
Would this, in a combination with a kill cord type switch(magnetic or mechanical),be a safe way of cutting power form the whole system during load without frying the electronics?
Hi! I have one. I want to try it in my new build. I didn’t check it under load. Without load, the voltage drop from 50 volts to 0 volts occurs in 3-4 seconds.
Thanks for You reply. Will be interesting to see how quick reaction during load! What type of switch will you use, the included one maybe not so good as kill switch?
Looks like a typical marine kill switch 
I installed the similar type on an outboard that did not had it by default from factory(grounding ignition).
