Player One CS to 1.25" Adapter (CS125)

Product Overview

The Player One CS-1.25 Adapter is a machined metal adapter that connects CS-mount hardware to the 1.25-inch thread standard. It carries CS female threads on one side and M28.5 × 0.6 male threads on the other, so a CS-mount lens or component can thread onto a 1.25-inch camera or accessory. Player One lists its length as 5 mm plus 2.5 mm of thread (7.5 mm total).

Who It's For

This is a good match if you use a CS-mount lens and want to mount it to a 1.25-inch threaded camera or imaging train — for example, pairing a CS lens with a guide or all-sky camera.

Key Features & Design

• CS female to M28.5 male: converts a CS-mount interface to the M28.5 × 0.6 (1.25-inch) thread.
• Compact length: 5 mm body plus 2.5 mm of engaged thread (7.5 mm total).
• Metal construction: machined metal body for a rigid, repeatable join.
• Mechanical only: no optical elements and no electronic connection.

Recommended Uses

• CS-mount lenses: attach a CS lens to a 1.25-inch threaded camera.
• All-sky and guide cameras: adapt CS-mount optics onto 1.25-inch camera bodies and trains.

Compatibility & Accessory Notes

One end is CS female; the other is M28.5 × 0.6 male, the standard 1.25-inch filter/accessory thread. It converts between those two standards only. If you are not sure whether your lens is CS or C mount, or how it will reach focus, send us your setup and we will confirm the fit.

Good to Know Before You Order

• Mechanical adapter only: it changes the thread interface — there are no optics and no electronic communication through it.
• CS to 1.25-inch only: it does not adapt other thread standards.

Frequently Asked Questions

Is it difficult to set up?

No — it threads directly between a CS-mount part and a 1.25-inch (M28.5) part with no tools.

What threads does it have?

CS female on one side and M28.5 × 0.6 male on the other.

Does it have any optics?

No. It is a mechanical thread adapter only.

Bottom Line

In short: a compact metal adapter that takes a CS-mount interface to the M28.5 × 0.6 (1.25-inch) thread, for putting CS lenses on 1.25-inch cameras and trains.