Watch out! You will become addicted to Eyelash Extensions!. You won't believe you waited so long to give eyelash extensions a shot. Extensions will last three - four weeks and from there get them filled in. Once you see your lashes, you won't be able to imagine your lashes without them! Don't forget your lash home care products such as mascara, lash cleaner, eyeliner and sealer. All available at Bella.