The original factory has filters, but they are difficult to buy.

Generally, a UV costs more than 800 yuan. The quality is the only one that can be matched with a Leica lens. It is also very good if you don’t have B+W, but you have to be careful that there are many fakes, and in fact, the 39mm small diameter ones are not easy to buy. The red mirror yellow one is for black and white. You have to order mirrors and another brand is Rodenstock