20/20

A 20/20 is a martial weapon with a perfect Sundering prefix or a caster weapon with a perfect Halves Skill Recharge and Halves Casting Time upgrades for the same attribute.

Occasionally, people use 20/20 to refer to a caster weapon set that has one upgrade on a wand and the other on a focus item or a wand/focus set that has either two HSRs or two HCT mods.