Polar ft60. This is a great tool to help during your workout. Knowing how many calories you burned is great, but most importantly you want to make sure your are staying in the proper heart rate zones to burn fat. This baby takes your weight, height, and age and factors out what your heart rate zone should be in 3 levels. Stick between zone 2 and 3 to get a great interval workout whether cardio or strength training. Use it and shed the pounds!