I have a Marconi F1216-04 dummy load, serial number 1050. It covers 8.2GHz to 12.5GHz and uses W/G 16.

It is made from brass, is air cooled and can dissipate 50W of RF with a maximum VSWR of 1.05:1.

It looks as if it has had a bit of a hard life as it is quite bruised and battered.