hello,waterproof refers to the surface of the filter has a waterproof film, if water drops on the filter, the water will directly slide off without leaving water marks on the filter, then it is easy to clean.we do not recommend that you use in the water, the water will enter the CPL inside the seam. 

Please check if the protective film of the PIR Fresnel lens has been removed. 

It's better to buy a cleaning fluid for lens filter. 

Dear K&F customer,We have warehouses in DE,UK,US,AU,CHN. We need to see what you are buying, and check the inventory of the warehouse where you choose to ship. Logistics delivery time depends on which country you are sending to. If the product you buy is in stock in our overseas warehouse, we will ship it directly from the local warehouse. But if the product you bought is not in stock in the local warehouse, then we will ship it to you from other warehouses. If the goods are shipped from a local warehouse, the logistics time is about 3-7 days. To ship from other warehouses, it will take about 3-15 days. Because of COVID-19, the efficiency of logistics will be slower than usual, please don't worry. I also notified the logistics company to deliver your package as soon as possible. 

I don't see why not, remember that the filter goes on the lens, not on the camera.