Hardware - Preventing Moisture, Vibration and Corrosion

[aitonos]

IP67 junction boxes paired with M12 breather plugs are a proven combination for marine installs because they solve the pressure‑cycling problem that quietly destroys “sealed” enclosures. The breather plug gives the box a controlled way to equalize during cold–warm transitions while still blocking spray and rain. Without that venting path, the internal air expands, forces its way out through the gasket, and then pulls humid air back in as it cools. Over time, that moisture condenses and ruins electronics. With the vent installed, the enclosure stays stable and dry.
The next step in the build is the enclosure Joinfworld Vented Outdoor Enclosure Box, WiFi Enclosure Waterproof Electrical Box 11.8x6.7x5.6 Plastic Clear with Mounting Panel Stainless Steel Dust Screen : Amazon.ca: Tools & Home Improvement . That box takes the same principles further by adding two important features: a flexible internal bladder for pressure equalization and a multi‑port rubber cable gland. The bladder handles expansion and contraction without relying solely on a threaded vent, and the gland provides seven independent sleeves sized for mixed‑diameter cabling while maintaining a watertight seal.
The cable set going into it—18‑gauge 12 V lines, waterproof Ethernet, NMEA 2000, USB GPS, and AIS—fits cleanly through the gland. The heavier battery cable gets its own drilled passthrough with the correct rubber bushing to preserve the enclosure’s integrity. With the bladder managing pressure and the gland providing disciplined cable ingress, this enclosure becomes a solid, marine‑ready base for the installation.  The only problem it’s like convincing a sumo wrestler to squeeze into skinny jeans “just for the photo.”

GREAT! didn't know that. I don't see the bresathing gland, where is located?

Thanks!

The gland is located in the middle of the long side of the box.  I posted a few pictures how i did it Jellyfish Hardware

Thanks, I guess it's the plate with screws, right? 

The box is very nice!