Ask if you want to know and ill get back to you. Its asking me to write more about myself but im not going to so instead im gonna leave a riddle feel free to answer it if you want. So anyways here it is..

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?