Abstract: An expendable immersion device for sensing characteristics of molten metal has a contact block and a receptacle tube. The contact block is slidingly disposed at least partially within a distal end of the receptacle tube. The expendable immersion devices includes a sensing element and a heat resistant tube. A distal end of the heat resistant tube is mounted to the sensing element. The sensing element extends partially into the interior of the heat resistant tube. A proximal end of the heat resistant tube is mounted over a distal end of the receptacle tube. A spring element is positioned over a proximal end of the contact block and abuts against the receptacle tube such that a force between the contact block and the sensing element is reduced when the heat resistant tube and sensing element are connected to the distal end of the contact block during assembly.