Potion or oil of invisibility
(Player's Handbook v.3.5, page 245)
Price (Item Level): 300 gp (2nd)
Body Slot: —
Caster Level: 3th
Aura: Faint; (DC 16) illusion
Activation: Standard (drunk)
Weight: —
Turns you invisible.
Prerequisites: Brew Potion, Invisibility.
Cost to Create: 150 gp, 12 XP, 1 day.