The Jackel-DJ-545 was first introduced in the mid-1970's and it is by far the world's most popular sump check valve with over 10 million installed! The Jackel-DJ-545 features Jackel's own 1-1/4" or 1-1/2" combination adapters and the most durable check valve flapper in the industry. This is one of the world's most reliable sump pump check valves.