The way the seal is designed being immersed will increase pressure on the seal and improve sealing. In addition, the connector pins on the box are hermetically sealed. If a connector is unplugged or fails, moisture that may seep past a wire seal wont make it past the box pins.
The mating connector is TE 1-1718646-1 You also need 6 pins and seals.
sockets : 7-1452665-1
I recommend a small bag of desiccant for long term deployments. Something like this is cheap insurance:
Anyone who has used potting in the past will understand how expensive, difficult and messy it is to waterproof. Also, you lose the ability to access your hardware once encapsulated. With this enclosure you have easy access to your IOT devices. This enclosure will be an enabler of rugged IOT.