The Turtles use Monster trapping gear during the fourth season of the 2003 TV series.
After the remains of the alien clones created by Baxter Stockman begin mutating creatures and humans alike, the Turtles use their new monster trapping gear in order to contain and capture the mutations. The monster trapping gear is specially designed to perform these functions without causing bodily injury that might result in the mutations splattering even more of the outbreak virus contaminant.
The Turtles first use the gear in the episode Insane in the Membrane. In the subway tunnels, the four Turtles battle to capture a group of mutant creatures. After clearing the tracks, they call it a day. During Adventures in Turtle Sitting, Leonardo, Raphael and Michelangelo travel to an electrical plant to contain a group of crablike mutations.