A pad includes an array of rigid elements that are grouped into rows and columns of the rigid elements, a plurality of flexible sheets disposed to alternate with the columns of the rigid elements, and a plurality of strings, each of which extends through a respective one of the rows of the rigid elements and the flexible sheets. A mobile device manufacturer embeds uninitialized secure elements into mobile devices. The valve lifter extends out of the valve chamber through the second valve seat bore to the electromagnet.