Sim/Tech Filter offers orifice shields designed to prevent drain media, such as drain stone, from blocking discharge holes. This is very important for keeping pressurized systems distributing effluent evenly. The shields have a sturdy design that keeps them firmly in place after snapping them on the laterals. The large amount of open area between the pipe and the shield allows for easy placement over the holes and reduces media clogging by debris. The enclosed design has a large amount of open area, but all openings are small enough to prevent media from entering the shield. Two styles are available — for top-discharge distribution holes and for bottom-discharge holes. Shields are available to fit 3/4-, 1-, 1 1/4-, 1 1/2-, 2- or 3-inch pipe. 888/999-3290; www.simtechfilter.com.