If you mean there is no chest strap monitor, then save your money and get one with a chest strap instead! The wrist watch only versions are pretty unreliable in comparison.
A few years ago I bought 2 cheap heart rate monitors for $14 each in a sale. They worked just fine, and when compared with my $300 Garmin they gave the exact same readings. Plus, leaving one in a gym locker, or putting it through the laundry by accident wasn't an expensive event. So, if you just want an instant read out of your heart rate I'd say buy cheap! If you want to record your heart rate during a workout and upload it to your computer you will probably have to spend ~$100, or buy a chest strap plus and adaptor for your 'smart phone' (total cost ~$60).