I wanna get a couple spare glo plugs(not the redcat brand) for my volcano Sv but there all different sizes and numbers and brands.

OS brand A3 or A5, A3 is a hotter plug. I live in michigan where it is cold and it runs great with the A3. Plus most hobby shops carry OS plugs

yes but it also depends on nitro % used. that can make lots of difference. generally the higher the %nitro, the colder the plug, OSA5,OSR5 and the lower the % nitro, the warmer the plug, OSA3,OS#8. But as you guys are in winter over there, the A3 being hot will indeed work well.