This green micro cache makes a great bison caches come with a rubber O-ring to seal it against the elements and with the split ring you can hang it from something, or even glue a magnet inside the base and make it a larger magnetic cache.  Made from anodised aluminium they are hard wearing and will last a long time.  Each one comes complete with a bolt log made with RITR paper.

Please note:  These have been painted and varnished in dark green paint to help them to not stand out when hidden.