colej That's "oversize", and will be charged a higher rate, based on size instead of weight.
48x6x6 is the limit for regular rates. The maximum cu.in. is something like 1728.
When I was selling a lot of 'longer than standard' drivers, I bought a bunch of 50x5x5, which is under the max, and the divers fit well, with h/c on.
**The maximum size for most mailpieces is 108 inches in combined length and girth. USPS Retail Ground pieces may measure up to 130 inches in combined length and girth (but will be charged oversized prices).
Dimensional price applies to low-density USPS parcels that meet these guidelines:
Using USPS Priority Mail, Priority Mail Express, or Parcel Select Ground
Addressed to all domestic Zones
Exceeds 1 cubic foot (1,728 cubic inches)
Packages that qualify for dimensional pricing will be assessed using the higher of these two rates:
Actual weight rate
Dimensional weight rate**
