7x7x6 size box with 3/4" thick insulated styrofoam. Styrofoam acts as insulation to keep you hatchling warm or cooled, depending on the season. It also prevents the box from collapsing or being crushed. I get my boxes from shipyourreptiles.com.
Two 32 ounce deli cups, 6.75" diameter. Make sure it has pre-punched holes and a lid. For most hatchlings you can get away with a 32 ounce deli cup.
For a 7x7x6 insulated box, you only need one heat pack. Do NOT use hand warmers or feet warmers for humans. These get way too hot, and they don't stay consistent in temperature. Make sure you use 40 hour UniHeat packs.
Moss is the substrate that your hatchling will travel in. It holds moisture pretty well, and acts as a nice cushion. I have been using this terrarium moss for years and it has worked great.
I use newspaper and sometimes paper towels.
Don't forget the tape. I can't tell you how many times I've started to prepare for shipping a hatchling and I don't have enough tape.
You should always soak the tortoise a few hours before packing them up. This hydrates them for the trip. It also allows them to go to the bathroom. I feed them mazuri the day of shipping. This holds them over for their trip home.
Fill the deli cup up with dry moss. Soak the moss with luke warm water and then squeeze out all the water. Place the hatchling inside the moss and place the lid on.
Place 2 sheets of newspaper in the box. Place the delicup in the newspaper and fold the newspaper over the delicup. This prevents the delicup from bouncing around the inside of the box.
Atttach the heat or cool pack to the inside lid of the styrofoam. I use the zip ties to hold it in place. For heat pack, make sure the red line is facing the tortoises. My temperature threshold for using a heat pack is if it’s going to be below 50°F at night. My threshold for a cool pack is if it’s going to be above 95°F in both locations. Always make sure you check the destination weather.
Always place air holes in the box. Regardless of the temperature. I use a Phillips head screw driver to poke two holes on each side of the box.
FedEx and UPS require a live animal waiver. You can get this from the source you created your shipping label. I use Shipyourreptile.com. I find them the best and their customer service is spectacular.