An improved seal-insert and seal for a toner hopper as used in toner cartridge assemblies for printers, copiers and facsimile machines. In one embodiment, the seal has two slotted, rectangular outer pieces joined together with slot alignment and joined by an inner layer of two-sided tape. The two-sided tape is made with a long u-shape which does not interfere with the slots in the outer pieces. The open end of the u-shaped tape configuration allows a seal to be inserted or removed from between the outer pieces to close or open the slots. The seal-insert is applied over the passage from the toner hopper. The outer pieces are made from an antistatic and/or a conductive material, such as an aluminum laminate or plastic imprefnated with conductive particles. Alternately, the outer pieces may be made from plastic covered with an antistatic and/or conductive spray or coating. In another embodiment, a tear-seal is made from antistatic and/or conductive material, and is provided with a tear-guide secured to and under the tear-sheet. The tear-guide has a width smaller than the tear-sheet and slightly smaller than the slot of the seal-insert. When the tear-guide is pulled by the enduser, the tear-guide will rip the tear-sheet in a straight line, providing an opening with an even width that will not block toner flow.