New Callaway Mavrik 5 Hybrid - Project X Catalyst 55 Senior Flex Shaft. Please let me know if you have any questions. Thanks and happy bidding! Elevate your golf game with the new Callaway Mavrik Hybrid. This state-of-the-art club features a Project X Catalyst 55 Senior Flex shaft, perfect for golfers of all skill levels. The 23-degree loft and 5H club number make it a versatile addition to any golfer's bag.