I think there are 'standards' which are listed somewhere in each company's manuals on 'crashworthiness'

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Something like must survive a 3' drop or so.
The biggest problems in packaging first using a box with too low a rating (boxes have a pound rating if designed to ship in, many boxes are designed for internal boxing only)...and the worst is packing edge to edge in a box. You always want to leave a crush buffers and have it strong enough to be stacked on, even if placed on it's side.
To properly package an item is usually not cheap. A decent box can be $2-$10 depending on size, and styrofoam / bubblewrap packing materials can easily run double to triple the box cost. Not to mention good tape and corner protectors if needed, etc.
I shipped two heads for a V8 and packaging alone ran $45 for proper double boxing in boxes rated for them....I had to ship them separately as well.
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