Two lights with spare batteries and bulbs are recommended. A head light is very handy during cave float trips, reading and plundering through your gear at night. Pocket Knife A camp-style knife with assorted tools is very useful. Not only are they potentially dangerous and unnecesary, but you could end up spending a lot of time chatting with the authorities at the airport. Sun glasses Bring these if you need them.
Polarized lenses are best.
It is a good idea to have a needle and thread, a few spare buttons, string and a bit of rip-stop tape to repair tears in your tent should that happen. Several sizes are a good idea for protecting camera , film, books and other small items. A larger plastic bag is also useful for last minute packing of wet shoes and clothes for the trip home. This can be a carry-on piece of luggage and used during field work. We will usually be drinking filtered rain water collected in large water vats.