THIS PRODUCT IS REALLY GOOD AND, ONCE INSTALLED, IT WORKS LIKE A BRAND NEW DOOR. SIMPLY REMOVE THE BOTTOM OF THE DOOR FRAME, USE A HOME MADE WOODEN WEDGE TO SPREAD THE THE FRAME AND RELEASE THE OLD ROLLER ASSEMBLY. SLIDE THE NEW ONES INTO PLACE AND REPLACE THE DOOR ON THE TRACK. VERY SIMPLE AND IT WILL WORK PERFECTLY. BE SURE TO CHOOSE THE RIGHT ROLLERS FOR YOUR DOOR AND REPLACE BOTH OF THEM AS A SET.