The most commonly used wheelchairs in India have 4 wheels. This model of wheelchair works well indoors. However, when taken outdoors it offers many problems as presented below. As a result people are restricted to within their house affecting their quality of life. Tricycles and wheelchairs with 3 wheels are good outdoors but they are difficult to use indoors because of their large width and length. The objective of the invention is to provide good outdoor mobility to people already having a 4 wheel wheelchair (which is a good indoor mobility device). This is achieved by an add-on device, the invention, which converts the 4-wheel wheelchair to a 3- wheel wheelchair (4 point of contact with ground to 3 point of contact with ground).