To create a more effective society for everyone by develop an unique product for society, this can be done through various steps. In this report, the projekt team has chosen to move forward with a product that is currently ineffective. Together with the company MiAB, which currently uses a common bicycle lock for its trailers, manufactures an electronic trailer lock. The purpose of this lock is to streamline the rental and to facilitate the user ergonomically. The aim is the report is to make the essential part of Freddy Olsson methodology as well as Stanford d.school: The Bootcamp Bootleg to take the already existing product and enhance its design and take into account of human needs and limitations. The report has produced a number of different product proposals that have later have been weighted with the company's requirements and wishes. The report has also made the necessary calculations to check that the new product meets all the different requirement that have been set up. The report has concluded that the new product is more ergonomic and smoother then the previous product and can confirm that all the requirements and wishes in this report has been fulfilled. This report will not deal with the electronics parts in this product and leaves that for another report and directs all the focus solely on the mechanical and design aspects.