I've had this harness for a long time and it does the trick. It's just two pieces of elastic. The longer piece is thin (1/4 inch?) and the short piece is thick (about one inch). If you're allergic to latex there's probably other materials you can use that are similar. The thin piece of elastic is cut to go around your body, the thick part is cut to go around the packer's shaft. Sew 'em together and you've got a harness.