For safety sake I wanted a turn signal buzzer on my 2008 S40. I removed the headlight rim and bulb. There is a lot of room behind the bulb and a generous cutout in back for the wires to enter and exit the headlight housing. I purchased 2 Radio Shack 12 VDC Piezo Buzzers 273-60. I simply soldered about a foot of automotive wire (two wires encased in a sheath) to each of the buzzers. I ran each set of wires through the headlight housing and using silicone rubber glued the buzzers to each side of the gusset on the frame behind the forks. I stripped away a small area of the insulation on each of the wires going to each turnsignal (inside the headlight housing), soldered and taped the connections. I used heat shrink tubing on the soldered connections at the buzzers. I was a little concerned that perhaps the buzzers with 86db might be too soft. They work great. The sound is not loud enough to be irritating yet loud enough to be heard. I used two buzzers rather than one thus not having to solder in a couple of diodes to isolate the lights.