A clicker is generally only used on a recurve bow and lets the archer know he has drawn the bow back to the correct draw length or to full draw. It gives an audible "click" and only on the sound of the clicker will the archer release the arrow.
GOLD LINE GOLD EXTENDED CLICKER
CAVALIER EXTENDED CLICKER
CAVALIER ADJUSTABLE CLICKER LH
CAVALIER ADJUSTABLE CLICKER RH
KLICKETY KLICK CLICKER