These heads are what they use in the samba schools of Rio. They consist of goat skin wrapped around and tucked into a wooden hoop while the skin is wet and pliable.
Each head is a slightly different color depending on the particular goat used. Keep in mind the photo might not be of the exact same head that shows up at your door.
Natural goat skin surdo heads sound terrific, and with a little extra care you can make them last a long time!
Skin heads (not skinheads, skin... heads) do not do well in the rain. It rains a lot in Rio so to deal with this they use plastic sheets that fit in between the rim and the head. You can find these available here.
Also, skin heads are very sensitive to temperature change. You will want to tune your drum for rehearsal and de-tune your drum after rehearsal to get the longest lifespan out of your head. This practice makes you a great tuner and you develop and great ear for tuning.