A countertenor is a type of classical male singing voice whose vocal range is equivalent to that of the female contralto or mezzo-soprano voice types.
Types of Compound Bows. Compound bows are classified by the type of cam system they use (called the bow eccentric.) The most popular types of compound bows on the market are Single Cam (sometimes also called One Cam or Solocam), Hybrid Cam, Dual Cam and Binary Cam. Less common designs like Quad Cam and Hinged are a little harder to find.
Find the maker of the compound bow and email the picture or serial number to the company, asking for a confirmation on the bow's year of production. Lists of compound bow makers are found at websites such as Hunter's Friend. Check a Bear bow (the name of the maker) for a series of different criteria to determine its age.