FEATURES AND BENEFITS: Allows the electrical contractor to comply with 2002 NEC Article 314-20. Levels and supports the wiring device where the box is set back from the wall surface. Works in handy boxes and 4" square electrical boxes with plaster rings for single switches or receptacle. Functions with all standard devices, switches and GFCIs. Manufactured from non-conductive, 105º C continuous use 94V0 rated flame retardant material for safer installations. Adjusts up to a 1-1/2" box extension. May be trimmed if necessary.