A compact cooling system includes a mounting panel adapted to receive a plurality of at least three cooling units, a cooling fan, and a fan drive mechanism. The caching appliance selects a storage area based upon the network protocol and stores the data packet in the selected storage area. There is also arranged a pump for circulating colored fluid in the fluid circuit. The slit apertures of the inner combined collimator and the septa of the outer collimator are arranged to define a plurality of apertures through the collimator assembly. Using the acceptable slop range, the system keep the net cost to the trader within the acceptable slop range, by regulating orders in the leg markets. The compensating pressure regulator for use with bottled gas on portable tools.