What ion does not have a voltage regulated gate?

Calcium ions (Ca²⁺) do not have voltage-regulated gates. While many ions, such as sodium (Na⁺) and potassium (K⁺), are controlled by voltage-gated channels that open and close in response to changes in membrane potential, calcium ions primarily enter cells through channels that can be triggered by other mechanisms, such as ligand binding or changes in intracellular signaling rather than direct voltage changes.