SBIG Baader 65mm Square OIII 8.5nm Filter

65mm square Baader OIII filter 8.5nm unmounted for maximum clear aperture in STX with STX-FW5 Filter WheelThese Narrowband 65mm Square Optical Filters are used with SBIG STX series cameras and FW5-STX filter wheels. These filters can be used with the camera's built-in guide sensor. Please note that 50 mm square filters are used with FW7-STX filter wheels.