Funster No : 20521
Join Date: Apr 2012
About Me: Me, Sharon, Bee (small person), 4 cats, and MoHo
Interests: Cycling; F1; cats; wildlife;
MH Type: A-Class
MH Model: Machzone Sovereign
Years Motorhoming: 1 year
Thanked 17 Times in 14 Posts
The 10 is 10x magnification, the 30 is the diameter of the lens.
10x is good, 30mm is a bit on the small side, restricting the amount of light they'll let in (on the plus side, they'll be compact); but for the price you can't go badly wrong I reckon (bear in mind you get what you pay for).
I have a pair of Opticron 10x42 which are really very nice, but cost me ten times that!