Caug7 chord for piano with keyboard diagram.
Explanation: The Caug7 is a four-note chord. Caug7 can also be written as C+7, C7+ or C7#5. Notice that Caug7 are identical with C7+5.
Theory: The Caug7 is an augmented chord extended with a minor seventh.
Notes: C - E - G# - Bb