The mezuzah is a protective case for a traditional Hebrew blessing. Mezuzahs serve as a reminder of God's presence in the world and as a sense of protection. Some people write their own blessing. A mezuzah is affixed on the right side of the door (as you enter the room), at an angle towards the room. It is customary to say a blessing when putting the Mezuzah up. These Mezuzah cases do not include the kosher Hebrew blessing scroll. They are mostly black with only a hint of glaze and are hand carved with the letter Shin.