Some smaller electric scooters, with handlebar hollows that are not round, require an adaptor to fit WingLights turn signals into their handlebars. You can check what type of handlebar you have either by removing the handlebar grip completely or cutting the end off.

If your electric scooter has a round hollow handlebar with a diameter between 14.7mm and 23mm, WingLights will fit in the handlebars without the need for an adaptor.