M.R.
Throw it in the garbage! You don't need any specialized equipment to work on your abs. Your own body weight is sufficient. Good ab exercises to do:
Stability exercises: plank, side plank, T-pushups, mountain climbers
Rotational exercises: russian twist, hip cross over, dumbbell chop
Trunk flexion exercises: crunch, elbow to knee crunch, raised leg crunch, v-up,
Hip flexion exercises: reverse crunch, leg lowering drill
Side flexion exercises: side crunch, side bend
Pick one exercise to do from each category and do 3 sets of 10 of each. Don't do ab work on consecutive days; you need at least 48-72 hours in between.
Finally, great crunch work will be meaningless if you don't have proper nutrition. You've got to be a clean eater to drop the body fat percentage to see the abs 'pop'.