nothing more than a sticker to cover up the slot I cut in the gauge face ..I am building that speedo with a digital MPH display and the sticker is from a MSM smart High frequency switch mode charger that I have used some parts from ,,, the sticker just fit to cover the hole and my son put it on so I left it till I am finished..I built the Tach speedo but it only counts miles I am rebuilding it to have MPH display