Abstract: Various embodiments described herein are directed toward input mechanisms, for input devices, configured to receive and removably couple to interchangeable elements. Handheld input devices applicable to some embodiments may include, without limitation, computer controllers, video game console controllers, and handheld video gaming devices. Input mechanisms applicable to various embodiments may include, for control sticks (e.g., joysticks or analog sticks operable by a user's finger, such as a thumbstick), buttons, switches, and directional pads. According to some embodiments, an input mechanism is provided comprising a base component, and an interchangeable element configured to removably couple to the base component. Depending on the embodiment, coupling different interchangeable elements to the base component may cause the input mechanism to vary in size, appearance, contour, material, or features provided by the input mechanism.