The #19831 Male Optec/DSI 3.5" to OPTEC-4300 male dovetail fits the telescope side receiver of the Gemini and allows any combination of our DSI 3.5-inch spacers to be easily installed on the telescope side of the Focusing Rotator.

Specifications

Compatibility

• Optec/DSI 3.5" Threaded Spacers.
• Gemini Focusing Rotator (typically used on telescope side).

• Inside Diameter: 3.165" (80.4mm)
• Outside Diameter: 4.95" (125.7mm)
• Overall Height: 0.83" (21.0mm)
• Clear Aperture: 3.165" (80.4mm)
• Weight: 4.8 oz (135 g)
• Back-Focus Usage: 0.1" (2.5mm)
• Drawing