In 1866 he started selling canvas trousers called Levi's and the miners bought them faster than Strauss could make them. Strauss soon received a lot of advice on ways to improve his jeans. In 1873 Jacob Davis him an idea to make the jeans even stronger by adding metal rivets to the pockets so that they would not tear. Strauss liked the idea and decided to use it. However, many people complained that the canvas was uncomfortable, so Strauss changed from canvas to a heavy denim material. It was dyed indigo blue and miners liked the new material because dirty marks did not show on the dark colour.