1.25 inch variable polarising filter for telescope eyepieces - Function: acts as a dimmer switch to adjust brightness of the view through the eyepiece - Benefit: reduces the brightness of the Moon or planets for clearer, more comfortable viewing - Performance: fine brightness control offers better performance than fixed-transmission filters - Brightness range: adjustable from 1% to 40% transmission by turning the filter housing - Compatibility and size: fits standard 1.25 inch telescope eyepieces and accessories - How to use: rotate the filter housing to set the transmission from 1% up to 40% - Use scenarios: - Moon observation at high magnification to reveal surface details without glare - Planetary viewing (eg, Jupiter, Saturn) to improve contrast and feature visibility - Observing in bright or urban skies where glare needs to be controlled for comfortable viewing