The equipment I use is mainly Nikon, chiefly two camera bodies, a Nikon D750 DSLR body and a Nikon Z6ii mirrorless body, with a variety of prime and telphoto lenses. The odds of two cameras failing is beyond slim (not had even one fail yet!) but I also carry a Nikon Z7ii mirrorless body as a belt and braces reserve. Cameras are fitted with dual memory cards set to backup, so each image is recorded twice. I also have several flashguns but try to use natural light whenever possible, modern digital camera sensors are much, much better in low light than film ever was and natural light gives a much better impression of the emotion and feeling of the moment. Occasionally I will also use flash for creative effect, rather than just supplying more light.