can of spinach question

[abraham]

the can of spinach magic item allows the user to gain +5 to strienth for about 3-6 rounds, now my question is what would the rarity level be?

[Ninja_Prawn]

Going by the ratings for Potions of Giant Strength, I'd put it on the borderline between uncommon and rare. Make it 1d6 rounds and it's comfortably uncommon. +6 Strength and it'd have to be rare at any duration.

Edit: assuming it bypasses the soft ability score cap at 20.