Niobium Foil
PartChecks the cold end of the resistance and susceptibility setups with its 9.2 K transition and supplies niobium for arc-melted intermetallics. Buy 99.8% or better, annealed, 0.1 to 0.25 mm thick so that strips can be cut with scissors. A full specification article for this item is being written. Meanwhile its bill of materials and connections are below.