The ESATTO 4″ → ARCO 3″ adapter for the Takahashi FSQ-106 telescope (PrimaLuceLab, SKU: PL3600469) enables a quick and rigid connection of the ESATTO 4″ electric focuser with the ARCO 3″ rotator/tilt corrector in the Takahashi FSQ-106 astrograph. CNC machined from a single block of aluminum, the adapter guarantees perfect optical axiality and maintenance of the back-focus budget provided by the manufacturer, thanks to which the whole works without vignetting even on full-frame matrices.
• dedicated fit: fits only the Takahashi FSQ-106 tube with the ESATTO 4″ extractor
• quick assembly of ARCO 3″ without additional spacer rings
• precisely turned locating surfaces – maintained perpendicularity and axiality
• anodized aluminum 6061-T6 in ESATTO/ARCO color – scratch and corrosion resistant
• short optical length (only 12 mm) – does not “eat up” valuable back-focus
• a set of M4 stainless steel screws ensures a secure, rigid connection
• ESATTO 4″ → ARCO 3″ adapter for FSQ-106
• set of M4 mounting screws (6 pcs.)
• quick assembly instructions
• telescope side: ESATTO 4″ collar (internal)
• camera side: ARCO 3″ flange (external)
• optical length: 12 mm
• Outer diameter: 120 mm
• material: aluminum 6061-T6, anodized
• weight: 180 g
• compatible telescope: Takahashi FSQ-106 (N/ED/EDX)
• manufacturer: PrimaLuceLab (Italy)
If you use an ESATTO 4″ electric focuser and plan to add the ARCO 3″ precision rotator to your FSQ-106, this adapter is an essential link. It ensures a secure, perfectly axial coupling of both devices, resulting in perfect collimation and full use of the imaging field of the legendary Takahashi astrograph.

