What does the 'H' (in a box followed by three other numbers) mean on a paypal shipping label?

[i.m.changkyuned]

I've seen 'C' and 'R' before (which I read mean city and rural as I've read) but this is the first time seeing an 'H' and am just curious since I've never seen it before out of hundreds of labels. 

Thanks!

[berserkerplanet]

Never seen an H either (always C or R), but it is routing information - Highway Contract Route

2.2Descriptive Prefix
The authorized descriptive prefixes and their abbreviations are “Carrier Route” (“C”),
“Rural Route” (“R”), “Highway Contract Route” (“H”), “Post Office Box Section” (“B”),
and “General Delivery Unit” (“G”).

https://pe.usps.com/Archive/HTML/DMMArchive20030810/M014.htm#Rei13232

(old document, but consistent, and I didn't bother looking for current info)

It wouldn't apply to only PayPal shipping labels - it's a general provision that should be observed for all PC Postage labels.

I just found one from a delivery to my PO Box address and it has a B as the routing prefix.

[lja440]

It is going to a Highway Contract Route. 

Highway Contract Route (HCR) - A route of travel served by a postal contractor to carry mail over highways between designated points. Some HCRs include mail delivery to addresses along the line of travel.

[muttlymob]

H is Highway Contract Route (usually the odds and ends of an area that doesn't easily fit into another rural route)

C is City route

R is Rural Route

B is PO Box