No, definitely do not write directly on the Perfect Crates. Since we reuse Perfect Crates and they will be rented by another customer after you, we do not allow any kind of altering of our Perfect Crates. However, we will provide you with a stack of Moving Labels that you can use to write down the room location and contents packed inside of each Perfect Crate. Just place the Moving Label on the identified area of the Perfect Crate that says, “Place Label Here” and you will easily be able to recognize what you packed into each Perfect Crate.