It is possible to insert wiring without the proper tool, but this requires great care to avoid damaging the connectors. For example, pushing a screwdriver down the middle of the block is a bad practice as it forces the two blades of the terminal post apart, leading to bad contacts. It is also possible to punch down multiple wires on top of each other in a single post of a punch-down block, but this practice is discouraged because of reliability concerns. If these multiple wires are of different thicknesses (wire gauges), it is even more likely that the thinner wire will develop contact problems. Similarly, stranded wire can be used on punch-down blocks, but they are designed for solid wire connections.