ZWO EFW 7-Position Electronic Filter Wheel (2 / 50.4 mm)

The ZWO 7-Position Electronic Filter Wheel (EFW-7x2") is a sleek, precision-engineered accessory that empowers astrophotographers to automate filter changes seamlessly. Crafted from aircraft-grade CNC-machined aluminum, it's ultra-thin (just 20 mm) and lightweight—only about 650 g—so it won’t overload your imaging setup.

Designed for versatility, it holds up to seven 2" threaded or 50.4 mm (±0.5 mm) unmounted filters (≤ 7 mm thick), making it ideal for mounting LRGB, narrowband or specialty filters. A whisper-quiet NPM stepper motor provides fast and accurate rotation, while USB-powered control via your camera or computer removes the need for external power supplies.

Compatible with both ASCOM and ZWO SDK-based software, the EFW-7x2" integrates effortlessly into popular astrophotography tools, enabling smooth automated imaging sessions.

• Capacity: 7 filter positions for 2" threaded or 50.4 mm ±0.5 mm unmounted filters (≤ 7 mm thick)
• Thickness: 20 mm (0.79")—ultra-compact design
• Weight: ~650 g (22.9 oz)
• Construction: CNC-machined aircraft-grade aluminum
• Motor: Quiet, reliable Japanese NPM stepper motor
• Control Interface: USB 2.0 (powered by camera or PC)
• Software Support: ASCOM and ZWO SDK compatible
• Backfocus*: with ASI6200 camera: approximately 18 mm

• ZWO EFW-7x2" Filter Wheel
• USB 2.0 Cable (2 m)
• M54(male) to M48(female) adapter (thin type)
• M54(male) to M48(female) adapter (flanged, +2 mm spacing)
• M54(male) to M42(female) adapter ring
• Filter carousel pre-installed
• Documentation and setup screws