These are legit mil-spec roto-molded transport cases (the kind the military uses for comms gear, medical kits, weapons systems, etc.). From the photos + your specs, these are not cheap consumer cases—they’re the heavy hitters.
What they are:
Ruggedized military transport containers
Rotationally molded polyethylene
Watertight / dustproof / buoyant
Steel latches, molded handles
Comparable to Pelican-Hardigg / SKB / ECS / Almar / Hardigg military line
Bright yellow/orange = common for medical, comms, or sensitive equipment
These are the kind of containers Uncle Sam paid thousands for new.
Size groups & realistic market value
1️⃣ Large long containers (2 units)
102” L × 40” W × 21.5” H
These are beasts. Commonly used for:
Antenna arrays
Litter systems
Long weapons / comms racks
Used resale value (each):
2️⃣ Medium upright containers (3 units)
42.5” L × 30” W × 27” H
Very desirable size for:
Tools
Camera/film gear
Medical & rescue
Overland / expedition builds
Used resale value (each):
3️⃣ Extra-large box (1 unit)
47” L × 48” W × 35” H
This is a high-cube container — excellent for:
Medical / disaster response
Marine use
Industrial storage