New Diezel Cab - thought it was 8 ohm but looks like 4 ohm

A few months ago I picked up a new Diezel 2x12 rear loaded cabinet with two vintage 30s to pair up with my Herbert head. When I ordered the cabinet, the dealer's site listed it as an 8-ohm cab, so when I received I just plugged into my amps 8-ohm jack and let it rip. The other day I decided to try my King Snake through the Diezel cab. Upon closer inspection, I noticed that the label on the back of the cab has 4 ohm written in marker on the back with the 8 ohm marked over (see the picture below).

IMG_1036 by bertniemi, on Flickr

I have been running to an 8 ohm load with no problems, but I guess I should probably be running to the 4 ohm load?

Plug a speaker cable into it and measure with a multimeter. Touch positive to the tip and ground to the sleeve. 8ohm should read anywhere from 6>8 ohms and 4 should be around 3

If you don't have a multimeter, you can check the speaker(s) itself. If it says 16 ohms, it's most likely an 8 ohm cab, if it says 8 ohms, it's most likely a 4 ohm.

What speakers does it have? Maybe it's K-100s which in that case it will be 4 ohms

Thanks guys! I took the jack plate off and shined a flash light in there, and it looks like it has V30s. This weekend I'll pull the back off and see how the speakers are wired. The cabinet sounds good, just curious why it was sold as an 8 ohm cab, but labeled as 4 ohm.