This DO-204AL package 1N4004 diode will work as a coil suppressor on relays. The cathode (banded end) goes to the positive side of the coil. The diode is rated for 400V reverse voltage, and 1A continuous current (45A peak).

 

This DO-41 package 1N4001 diode will work as a coil suppressor on relays. The cathode (banded end) goes to the positive side of the coil. The diode is rated for 50V reverse voltage, and 1A continuous current (30A peak).