Xiaomi Button

This is a few inches in diameter and triggers when pressed down for a few seconds.

Elko ESH Plus 316GLED RF PH

316 GLED dimmer is designed for LED and low loads, dimmer also incandescent lamps, halogen, electronic trams. ELKO Plus version comes with light ring for light around the dimmer button.

Aeotec Doorbell

A Z-wave doorbell that can also act as a customizable door chime and siren. You can add custom sounds over USB from any computer.

Amazon Dash Button

Use these buttons to control pretty much anything in Home Assistant using an open source program called Dasher.

Fibaro The Button FGPB-101

A Z-Wave scene controller to control individual devices or smart home scenarios. Different actions may be triggered with one to five clicks or by holding the button down.

Aeotec ZW130-A WallMote Quad

Wireless Z-Wave wall switch and remote control that can control up to 16 different scenes via tap, tap and hold, slide up, and slide down. Attaches to wall plate with a magnet.

Z-Wave.Me Radio Wall Switch ZME - Wallc S

With this product, Z-Wave devices can be controlled directly, as well as different scenes can be activated in a central controller.

Flic Smart Bluetooth Button

A simple and stylish wireless button that acts as a shortcut to your favorite actions on your phone.