SBIG Baader 50mm Square 8nm SII Filter

50mm square Baader SII filter 8nm unmounted for maximum clear aperture without self-guiding in STX.These Narrowband 50mm Square Optical Filters are used with SBIG STX series cameras and FW7-STX filter wheels. These filters are compatible with the STX Guider. Please note that 65 mm square filters are used with FW5-STX filter wheels.