Parfocalizing rings

A highly recommended focusing aid for all types of focusers
especially helical.
( 2" ID. , 2.375" OD. x .250" thick )
for 2" eypieces
( 1.250 ID. , 1.5" OD. x .200" thick ) for
1 1/4" eypieces
Both rings supported by 2 set screws.
"Not recommended for eyepiece
barrels with Undercuts"