An LED light is useful if you will be using the scope in a
dark room because you're not dependent on the ambient light of the room. The
LED is affixed to the end of the scope over the object cell. Because
the LED is so bright, stained glass is used for the object cell glass to
diffuse the light.
To turn the light ON, simply twist the base of the unit CLOCKWISE. To
turn the light OFF, simply twist the base of the unit COUNTER-CLOCKWISE.
The battery life of the lighting unit is 36 to 48 hours. It has a 2 year shelf
life with fresh batteries. Batteries are a "coin cell" which
can easily be found wherever batteries are sold. The scope is sold with two
batteries, but only one is required to operate.
Bearings allow you to turn the end of the kaleidoscope instead of the entire scope when you are viewing the image. Bearings are nice, but not necessary. They are nicer when you are viewing chorus lines and you want to keep the image vertical while it changes colors.
Scopes with LED lights or bearing ends require a slightly larger size and will be 1-7/8" x 1-7/8" x ~10".