Sky Mentor 1.25" Variable Polarizer Filter - TA189 classic This adjustable speed electric motor

This adjustable speed electric motor drive installs easily onto the Focusmate 10:1 fine focus unit

Typical eyepieces used with fast Newtonians can have field stop locations differing by as much as half an inch

it's made for the business end of your optical devices

Easy to install on existing Telrad Finderscope

With its 55 lb load capacity

Sky Mentor 1.25" Variable Polarizer Filter - TA189 classic This adjustable speed electric motorAdjust the brightness level of the Moon, Venus, and other bright objects with the Sky Mentor Variable Polarizer. A standard Moon Filter is similar to a pair of sunglasses. They work fine, but sometimes the scene is too dark or too bright, and theres not a lot you can do about it. A variable polarizing filter is much more flexible than a Moon filter. It allows you to set the percentage of attenuation by turning the top section of the two piece filter.