The county and the freight
Macomb County took 65% of Michigan's federal defense contract dollars in 2024, $3.21 billion in contracts, and has more than 1,100 aerospace and defense companies. Its employment concentration in military armored vehicle and tank component manufacturing is 6.72. SAPA Transmission announced a roughly $163 million, 200,000 sq ft plant in Shelby Township with at least 328 jobs, making transmissions for military vehicles.
Heavy parts do not need volume. They need a floor and walls that do not give. A shop that ships a few dozen boxes of gears at a time wants a box whose bottom does not fail under 1,800 lb of steel. That is why this trade is full flap bottoms and 4- or 5-wall construction.
Specs for dense parts
| Choice | Why | Cited range or note |
|---|---|---|
| Full flap bottom | Flaps overlap into a solid base | Full-flap boxes typically support 1,100 to 2,500 lb by wall construction |
| 4-wall | Between triple wall and 5-wall | 1,500 to 2,200 lb cited |
| 5-wall | Highest cited capacity | 2,000 to 3,000 lb cited |
| Short height | Floor load before volume | 48 x 40 x 24 in |
| Liner | Oily or machined parts | Poly liner inside; see lids and liners |
What we need from a shop
- The loaded weight of one box, as near as you can weigh it.
- The footprint your pallet or rack takes.
- Whether the parts are sharp, oily or finished. It changes the bottom and the liner.
- How many, and when.
Read 4-wall and 5-wall before you ask. They say what the cited ranges are, and they say where the stamp matters. Then use the spec finder to see whether your weight is in range.
A note on regulated parts
Defense work has its own packaging rules. We do not know yours. If your parts need certified or marked packaging, a used box is not the answer. Ask your packaging engineer, and write the part in the request if a used box is acceptable.
Facts and figures
- Container Exchanger gives common gaylord heights of 30-36 in for 2-wall, 34-40 in for 3-wall, 36-41 in for 4-wall and 36-46 in for 5-wall boxes. (blog.containerexchanger.com, retrieved 2026-11-10.)
Terms
- full flap bottom: Bottom flaps that overlap to make a complete base; best for heavy loads, powders and small parts.
- wall count: How many layers of corrugated board form the side walls, from 2 to 5; more walls, more stacking strength.