Developed by Bill Lind after his stroke, Leveron converts all standard doorknobs to levers for people with hand, wrist or visual problems. It comes in one size that fits all inside and outside doorknobs and can be installed quickly without removing the existing doorknob. It costs approximately $14.95 and comes in many colors, including one that glows in the dark. Leveron meets ADA quidelines. To purchase call the manugacturer directly at (781) 237-8177 or go to OR .