The Player One M48 Female → M48 Male 17.5 mm Spacer Adapter (SKU: POA-M48F-M48M-175) is a precision extension ring designed for back-focus adjustment in optics with M48 × 0.75 thread. The optical length of 17.5 mm allows you to easily achieve the standard 55 mm (e.g. with reducers or flatteners) in sets with Player One cameras, filter wheels or FD MAX drawers.

Key Features

• input thread: M48 Female (M48 × 0.75)
• Output thread: M48 Male (M48 × 0.75)
• optical length of exactly 17.5 mm – a convenient addition to your back-focus budget
• made of lightweight, anodized 6061-T6 aluminum, resistant to corrosion
• matte black interior, reducing reflections and improving contrast

Technical specification

• thread (telescope side): M48 × 0.75 – female
• thread (camera side): M48 × 0.75 – male
• optical length: 17.5 mm ± 0.05 mm
• Outer diameter: 52 mm
• material: aluminum 6061-T6, anodized
• weight: 24 g

The 17.5 mm spacer in the M48 thread is a simple and reliable solution for precise setting of the working distance in modern astrophotography setups, especially when using Player One cameras and correctors / reducers requiring an exact 55 mm back-focus.