width of the upper conductive layer 52 and the underlying insulating layer 51 provides accessibility to the lower conductive layer 49 for suitably formed connectors for supplying or utilizing electrical power the plastic bar 48 along with the various conductive and insulating layers 49 51 52 can be applied to the tee 10 in the factory after the tee is rolled or otherwise fabricated or can be applied in the field before or after the grid is installed fig1 illustrates an elongated insert assembly 56 proportioned to snap into the novel grid tee 57 shown in fig3 the insert 56 which runs the full length of the tee 57 includes an insulating channel 58 including a web and legs permanently attached to the opposed legs are associated opposed conductors 62 the conductors 62 can comprise any of the foregoing described conductor compositions the legs are proportioned to be frictionally held or mechanically captured within the interior of the depending channel formed by the flange of the tee 57 more particularly hems 63 formed by folded in edges of the sheet stock forming the tee 57 underlie the distal edges of the legs so as to mechanically capture the insert 56 within the tee channel a connector block 55 preferably molded of a suitable plastic is proportioned.