Culligan D-40A filter cartridge (Crestwood, NW DC)

This is unwrapped but essentially unused: I installed it in our Culligan under sink water filter (model US-600A) but then the casing was leaking when I turned the water back on. I probably just needed a new O-ring, but the old one *seemed* fine so I tried tightening the casing more… and overdid it enough to fracture the casing threads. So had to get a whole new filter and went with a different model. Happy for this $50 cartridge to be used and not go to waste.