A locking device for preventing the movable plate from disengaging from the fixed portion of the magazine includes a substantially V-shaped lever which includes an operation end, a contact end and a pivotable end which is located between the operation end and the contact end. The barrier system includes rail portions, connectors, and cover members. The offset index value is used to index the offset lookup table to obtain an offset value. Embodiments disclosed herein also relate to temperature compensating a programmable duplexer based upon one or more temperature indications. The terminal includes a plurality of branched terminal portions at a position corresponding to an interior of the through-hole, and at least one of the branched terminal portions is bent and attached to the printed conductor. The impactor can be readily used with existing directional boring machines.