State any four essential features of bill of exchange.

The four essential features of bills of exchange are:

1. It must be a written document.

2. It is an unconditional order to pay by the drawer to the drawee.

3. The maker of bill must sign it, without which it will not be a legal proof.

4. The amount to be paid along with its expiry date must be specifically mentioned (both in figures and words) in a bill of exchange.