Friends of Hue Smart Switch: Philips Hue Wireless Switch and Dimmer (No Batteries, No Charging, Exclusive to Philips Hue Lights) – Glossy White, anthracite : Amazon.de: Business, Industry & Science
Product Catalogue - Radiofrequency: Zigbee Friends of Hue RF switch - 03906 - Surface mounting equipments - Vimar energia positiva
Much quieter Friends of Hue switch with button cell: comparison with the EnOcean module - Hueblog.com
Product Catalogue - Radiofrequency: Kit Friends of Hue+plate EikonEvo white - 0K03906.03 - Surface mounting equipments - Vimar energia positiva