Punch-down block

[1] The exact size and shape of the tool blade varies by manufacturer, which can cause problems for those working on existing installations, especially when there is a poorly documented mix of different brands.

Punch-down blocks are often used as patch panels, or as breakout boxes for PBX or other similar multi-line telephone systems with 50-pin RJ21 (Amphenol) connectors.

Often a separate tool known as a spudger is used to remove small stray pieces of cut off wiring stuck within punch-down blocks.

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.

In addition, punch-down blocks are being used to handle larger numbers of faster data signals, requiring greater care and proper procedures to control impedance and crosstalk.