Is "Hextech Mystery Champion Permanent" something like "super Hextech Mystery Champion Shard"?

Hi. I scored only 4 starlight tokens from last Star Guardian event & there's only ~2 days until they will disappear. I actually plan to buy that "Hextech Mystery Champion Permanent" but I'm not pretty sure how it works? :S I mean - Will I get something like shard in my "LOOT" & then I can use this when I want - even in future or far future? OR this works like "mystery skin"(?) & when I'll buy it, I'll immediately got a champion & my "Hextech Mystery Champion Permanent" will disappear immediately? :S