Telescope Focuser customization 3.5'' Double speed High load zero displacement | eBay
SkyWatcher Explorer-200PDS (200/1000) Newtonian reflector OTA with Dual-Speed focuser (1:10) on EQ5 mount with 9x50 finder, 28 mm APEX eyepiece - Budapest Telescope Centre
Teleskop-Express: TS-Optics Dual-Speed Unit for 2.5" RAP focusers