Same Either Way

Riddle: Pronounced as one letter, And written with three, Two letters there are, And two only in me. I'm double, I'm single, I'm black, blue, and gray, I'm read from both ends, And the same either way. What am I?

Answer: An eye.

Source: https://www.riddles.com/index.php/177

Pronounced as one letter, And written with three, Two letters there are, And two only in me. I'm double, I'm single, I'm black, blue, and gray, I'm read from both ends, And the same either way. What am I? — Same Either Way by Anonymous v1.

Riddle: Pronounced as one letter, And written with three, Two letters there are, And two only in me. I'm double, I'm single, I'm black, blue, and gray, I'm read from both ends, And the same either way. What am I? Answer: An eye. — by Anonymous v2.