Wireless button on handrail or wall mounted for bus/coach - Vignal| Vignal Group
A Wireless, Long-range Big Red Button Powered by a Coin Cell Battery
WiFi Switch (Works with Apple HomeKit) | Smart Home | myStrom
GoveeLife Wireless Mini Smart 6 Button Sensor, Group Control Multiple Devices, Versatile Control Button, Battery Powered, Supports Most Govee Smart Products - Amazon.com
ESP8266 IoT Wifi Button - Home Automation - openHAB Community
Battery-free Wireless Dome Button
Wireless Push Button - HeathZenith
Aqara Wireless Mini Switch, Requires AQARA HUB, Zigbee Connection, Versatile 3-Way Control Button for Smart Home Devices, Compatible with Apple HomeKit, Works with IFTTT - Amazon.com
Building Wi-Fi Buttons with ESP8266 · Alex Meub
Amazon.co.jp: 2 Button Wireless Remote Control / Accessories / Remote Control Switch Press 1/2/3/4/6/8/10/12/15/16 Keys : DIY, Tools & Garden