I found a couple crates of preserving jars at the local dump. For over a century this town has been burying rubbish in big holes in a nearby piece of land and if you're quick you can find treasures. These are Fowler's Vacola jars which is an Australian standard preserving system. Unlike Ball jars the lids have a rim that goes over the lip of the jar. The rubber seal is a band that fits in a groove and the lid is held on during preserving with a spring clip.