It is without a shadow of a doubt that the PUR 4OUR was and still is our best selling wheels to date. In an effort to continue offering truly high quality wheels, we have taken a step back to revise the PUR 4OUR for 2015. The PUR 4OUR.LS is a lighter version of the design, yet equally as strong. We have not comprised a single ounce of structrual integrity but instead have pin pointed the exact spots in which weight could be shed. At a first glance, the 4OUR.LS does not look any different but when getting up close and personal, you can see that the area which the spokes meet the inner barrel have been shaved. This on average, sheds about 3-4 lbs of uncessary weight.