This is a 99,995% pure Zinc anode for electroplating. These anodes are a nominal 250g of Zinc each, they vary several grams either way.
This anode is 64x30mm by around 20mm thick.
These have a 3.5mm diameter hole pre-drilled in the top to make it easy to use a tec screw or iron nail to attach a clip or clamps, as long as the item is iron or zinc it won't affect plating (it should be out of the solution anyhow).
These mostly have a few spots of slag or oxide on the back from casting, this will not effect the end use although you can wire brush it off if desired.
This anode is ideal for the hobbyist electroplater or small scale plating production runs, one of these will plate a lot of metal.