Kujlarson Model 10 Closer 51

Introducing the platinum storm door collection with a hidden closer and patent pending click&hold™ technology. The closer is built into the storm door and out of sight, enhancing. Meet the next generation storm door with a hidden closer. Introducing the industry’s first fullview storm door with a hidden closer and patent pending click&hold™ technology. Included in hidden closer kit with part number:

I purchased a home with a larson storm door with a larson model 10 hidden closer. The closer mostly works, but if you don't open it for long enough, it will slam, as if whatever damping.