The 16 Products Every Diehard MAC Junkie Should Own

A gel eyeliner is the most versatile tool in your makeup kit. You can use it to define eyes and brows or use it as shadow in a real pinch. MAC Pro Longwear Fluidline Gel Eye Liner in Backtrack ($19) is an essential for any MAC-lover because it goes a step beyond waterproof. It lasts all day — promise! The color isn't extreme black. It dries down to more of a gray, which works for an everyday eyeliner.