A convex cap for removable attachment to a barrel end of projectile firing equipment such as the end of a gun barrel, purposed to protect the interior of the projectile firing equipment from foreign matter such as dust, dirt, debris and moisture wherein the cap is adapted to be in place on the barrel end at the time of firing. The present invention offers a device and a method for handling security in a computer system comprising an existing organizational directory. The digital signal then has the benefit of using the picture improvement circuitry located within the analog module and there is no need to modify the analog module which has been in the cost optimization process for years. A heat transfer member is in contact with the unit batteries.