The 737 Skyhawk Duck Call is the progression from the DOS double reed that you've come to love over the years. This call features a louder tone with a lot more hold on the bottom end for those soft, subtle quacks and subtle feed calls. It has a slightly wider bore than the DOS which allows you to get aggressive and loud on the top end. If you're somebody that's been running the DOS over the years, this call is the perfect call to progress into next! FeaturesDouble reedLouder toneSlightly wider bore than the DOS