On the button and To a T

On the button adjective - Being precise with regard to a prescribed or specified criterion.

To a T and on the button are semantically related in accurate topic. In some cases you can use "To a T" instead an adjective phrase "On the button".

To a T adverb - In every detail.

On the button and to a T are semantically related in accurate topic. Sometimes you can use "On the button" instead an adjective phrase "To a T".