Kowa TP-105FT Protective Filter

I was a little nervous about adding extra glass in front of the lens, but the coating on this filter is so clear I honestly can't see any difference in brightness or sharpness. It fits snugly and gives me real peace of mind when I'm out in dusty or wet conditions.

The threads engaged perfectly on my scope's objective ring, and the glass is so clear I almost forget it's there. It gives me real peace of mind against dust and scratches during long birding sessions in the field.

I was pleasantly surprised how securely this filter screws onto my scope—no worrying about it loosening mid-observation. It’s saved my lens from scratches during a couple of dusty outings already.