lumicon - Low-Profile 1.25in Focuser for Newtonian on 3inch Base with 2.25 inch hole pattern

The Lumicon Low Profile 1.25" Focuser for Newtonian on 3in Base is a high-precision, pin-and-groove type helical focuser. The
draw-tube does not rotate. The low-profile design quickly and easily converts your standard Newtonian to a camera-ready telescope.
For visual use, the smooth focusing brings out the very best in your telescope's optics.  Accessories that take up back-focus,
such Lumicon's popular 1.25" Multiple Filter Selector, can be used with ease and convenience.  The U-groove base aligns and sits
flush on any telescope tube with a radius of 3.5" or larger.

Specifications:

Focuser Minimum Height Above Tube*
    1.75" (for 3.5" radius tube)
    2"    (for flat-base mounting)
Turns ratio: 2 per inch
Travel: 1"
Resolution/Backlash: < 0.0005"
Image shift: Negligible
Reverse action: Negligible
"Stiction:" Negligible

Footprint: 3" square
Hole Pattern: Square; 2.25" center-to-center
Min/Max Focuser Hole diameter: 1.5"/2.7"
Operating range: to 20°F/- 7° C
Maximum recommended load: 3 lb.
Mounting Hardware: 8-32, included

*Precise minimum depends on radius of tube.

Note:
Visual use of the Low Profile Focuser requires either the Lumicon 1.25" Multiple Filter Selector, LF5010, or a 1.25" extension
tube, such as the Lumicon LA1020.