This base designed by Astro-Physics has a dual-radius curve, letting it fit onto the predrilled holes of all Astro-Physics refractors or other commercial telescopes that utilize the same hole spacing. Luckily, the spacing between the holes of most finder brackets are the same.
The dovetail design of this base accepts the following items:
- 10 x 60 Quick Release Guider Bracket (S1060QRGB)
- 10 x 60 Quick Release Finder Bracket (S1060QRM)
- 8 x 50 Quick Release Finder Bracket (S850QRM) - discontinued
- Male Dovetail Base (A3251-B and earlier versions) along with whatever accessory you have attached
- Modified TeleVue StarBeam (STARFMD) or modified Qwik Point finder, which already includes the Astro-Physics part A3251-B male dovetail piece
The bracket is attached via 2 screws; the second set of attachment holes is provided for shifting the base forward or backward as needed. This base can be easily rotated 180 degrees for either right- or left-handed use. There is also a central locking screw hole so that the traditional Astro-Physics finder brackets can be used with this base (all you have to do it shift the forward thumbscrew back). The included stop screw can then be installed at the end of the base for use with these brackets. It is NOT used with the Guider Bracket.
Beginning in October 2013, Astro-Physics started to ship bases that were approximately 3/8" (9.5 mm) taller, allowing the guide bracket rail to more easily clear the mounting rings of Astro-Physics refractors. This allows the scope to rotate with plenty of clearance.
The mounting hole spacing is approximately 1 3/8" (34.9 mm) side-to-side and uses 10-32 x 5/8" Phillips Pan Head screws for attachment. Length is 2.3" (58.4 mm) and height of the bottom of the dovetail above the radius of the base's foot is 1.25" (31.8 mm). A 1/4"-20 tapped hole on the bottom of the QRBASEG can be used to attach it to a dovetail plate.