Widely used in fresh and salt water for taking samples of hard bottoms such as sand, gravel, consolidated marl or clay, this is a deliberately heavy device for biting deep into the bottom and has proven success at animal recovery. The simple design means it is simple to use. Heavy duty hinges and hinge pin can absorb thousands of bottom impacts. Self-closing scoops have center pivot closing action. When the scoop strikes the bottom, their tapered cutting edges penetrate well with very little sample disturbance. An attached underlip wipes the scoop clean of pebbles and cobble that would interfere with closing. By the same token, removable side plates prevent the lateral loss of sample as scoops close.
This well-regarded self-closing sampler uses a patented spring-load pinch pin that releases when cable or line slackens. A safety pin replaces the pinch-pin when not in use to prevent injury. Removable screens on top of each scoop allow water to flow through as it descends. This lessens the frontal shock wave and reduces surface disturbance. Both screens are covered with neoprene rubber flaps that close during retrieval.