During the 1950s and 1960s, the development of specific angling tools for bass significantly increased angler bass catches and helped stimulate the development of the sport. Some of these innovations include the invention of monofilament nylon fishing lines, the fiberglass (later graphite composite) fishing rod, the electric trolling motor, the fish finder/depth locator, and new artificial lures and baits made of various plastics. Recently, advanced electronics that mimic the sounds of schooling bait fish have been introduced, and a controversy has arisen over the proper use of these devices in bass tournament fishing.