These tiny surface mount buttons are dual-action! That means that when you push the button in you slightly you will connect between the common pin (C) and switch pin 1 (1). Then as you continue to press further there will be a tactile switch action that connects between common pin (C) and switch pin 2 (2).
These switches are perfect to replicate the feel of a trigger switch in many classic gaming controllers. These are used frequently in the Nintendo Wii portablizing community found at BitBuilt.
A 3D model for this switch was created by @tht1Asian and @deezy over on BitBuilt and can be downloaded here: 3D Model for TMHF07