The use of licenses is monitored in a computer or communication system which has a plurality of terminals and in which at least one license is associated with at least one user. The SAP particles are most preferably hydrated with an aqueous flame-retardant solution. Firstly, a capacitor is charged by the temperature dependent current source. Each secondary transition surface may begin at a primary transition surface and end at an angled surface. Multiple communications channels at different frequencies are provided which are synchronously switched between during a communications session by both devices. These proportions provide a uniform, durable and reliable retaining surface to the pin which is particularly useful in applications where the host material is harder than the pin.