A cable restraint system to route a cable through a test instrument housing, comprising: a device base, including: a base plate having a locating hole formed therein; and at least one mounting post disposed on the base plate; and a cable restraint device configured to route the cable through the test instrument housing to a termination point, the cable restraint device including: a base portion having at least one mounting column structured to receive the at least one mounting post, a pair of opposed sidewalls defining a trough structured to receive the cable, and a protrusion structured to engage the locating hole to maintain an orientation of the cable restraint device with respect to the device base; a flexible insert received in the base portion and disposed between the pair of opposed sidewalls; and a top portion structured to span the pair of opposed sidewalls to retain the flexible insert within the base portion and structured to engage the at least one mounting post, wherein the top portion lightly compresses the flexible insert, exerting a pressure on the cables, when the top portion is locked to the base portion by the mounting column engaging with the central hole. a device base, including: a base plate having a locating hole formed therein; and at least one mounting post disposed on the base plate; and a base plate having a locating hole formed therein; and at least one mounting post disposed on the base plate; and a cable restraint device configured to route the cable through the test instrument housing to a termination point, the cable restraint device including: a base portion having at least one mounting column structured to receive the at least one mounting post, a pair of opposed sidewalls defining a trough structured to receive the cable, and a protrusion structured to engage the locating hole to maintain an orientation of the cable restraint device with respect to the device base; a flexible insert received in the base portion and disposed between the pair of opposed sidewalls; and a top portion structured to span the pair of opposed sidewalls to retain the flexible insert within the base portion and structured to engage the at least one mounting post, wherein the top portion lightly compresses the flexible insert, exerting a pressure on the cables, when the top portion is locked to the base portion by the mounting column engaging with the central hole. a base portion having at least one mounting column structured to receive the at least one mounting post, a pair of opposed sidewalls defining a trough structured to receive the cable, and a protrusion structured to engage the locating hole to maintain an orientation of the cable restraint device with respect to the device base; a flexible insert received in the base portion and disposed between the pair of opposed sidewalls; and a top portion structured to span the pair of opposed sidewalls to retain the flexible insert within the base portion and structured to engage the at least one mounting post, wherein the top portion lightly compresses the flexible insert, exerting a pressure on the cables, when the top portion is locked to the base portion by the mounting column engaging with the central hole.