Purple Ring Body Light  Body Lights or blinkies use two CR927 lithium batteries (included   and installed) These magnetic flashers can be worn on the body   or clothing using the included magnets. One magnet is part of   the blinky and the other detaches and attracts to the first,   securing the flashing pins to the clothing or ear, etc. They   can also be worn as a necklace with our lanyard   attachment (sold seperately) or as a lapel pin with our   backer   pin (also sold seperately.) Don't be surprised to find extra   goodies in your order. Magic Matt includes samples, freebies,   goodies and gifts in many orders solely at his discretion. Extra   batteries are almost always included and related samples are   tossed in when possible. Thanks for your business. Disclaimer:   This product is not suitable for children under 5 years of age.