Make it easier to see the path of your arrow and retrieve it after the shot with BlackOut® Lighted Nocks. Featuring a trustworthy, patented linear switch design, this wire-free design activates with the push of your bowstring every time. Convenient opening in the side of the nock makes it easy to switch the light off with a small screwdriver or tip of most broadheads after you retrieve your arrow. Runs for 20+ hours on its lithium battery. Bright design for easy spotting in daylight or darkness. Weighs approximately 15 grains. Precision lighted nocks for arrows; Trustworthy, patented linear switch design - wire-free design ; Activates with the push of your bowstring; Easy-to-use nock design - deactivates with a small screwdriver or broadhead tip; Lithium battery - runs for 20+ hours; Easy-to-see design; Approximately 15 grains;