An energy storage system is described that includes at least one body (10; 10 ) that is arranged to move along a bore (110; 110 ) that is excavated underground. The energy storage system includes a seal assembly within the bore (110; 110 ). The seal assembly(19 27;19 27 ) includes a support member (19; 19 ) and a se...

A method of forming a belt (5) for a face mask (1), comprising the steps of: using a measuring means to trace the contours of the face of a user, and using the data collected by the measuring means to create a cut line on a loop of material (5); wherein the step of using a measuring means to trace the contours of th...