The Bleak by Doomsday Discs and is a popular, straight-flying, beadless putter with a shallow rim feel. The Ration plastic is the baseline, grippy plastic which may not last through the apocalypse, but an affordable stack will keep you going for years to come. It is also available in longer-lasting premium blends that have slightly more glide. The future may look bleak, but your putting doesn't have to. 

The Bleak is PDGA Approved