I am going to order an Omnium crankset, it's a 130bcd. For the road I'll use the 48T and 25mm tires. I want to get another wheelset with wider rims and 38-40c tires for off road (frame fits up to a 45 at least). I might even do some CX races on it.

My question is if I want to get a 38T ring, which I understand is the smallest I can go, is there a single speed specific one I need? I was looking at SRAM and all I see is Red/Force/Rival, I don't know if that's what I need. I was also looking at a Wolf but it says it's for 10-11sp chains. I'm just confused on if they work with a SS crank and 3/32 chain.

Omniums are not 130bcd.

A narrow chain ring will work with a wide chain but not vice versa. So you can put a 1/8 chain on a 3/32 chain ring, but not a 3/32 chain on a 1/8 chain ring. If you make the effort to search for 1/8 chain rings, they are available.

maybe you mean s300 crankset

Yeah, that's it. I got them mixed up.