Bus Termination Card Model TERMIN provides termination resistor networks for passive AT-Bus backplanes that do not already have termination networks installed. If those backplanes are not properly terminated, reflections and standing waves can prevent proper operation of cards plugged into the backplane and even prevent operation of the computer. This is particularly true when the backplane is in an expansion chassis and ACCES; Model ETRC-AT and PTRC-AT are used to expand a computer's bus into that expansion chassis. Proper termination is especially critical when there are more than eight slots in the backplane. Many backplanes provide pads for SIP resistor networks to terminate computer-bus lines but some do not. If your backplane doesn't have provision for termination networks, then TERMIN is a viable alternative. The card is 6.42" long and seated height is 1.2".