When the grab touches the bottom, inertia from a self-contained weight releases a catch and helical springs rotate the inner half cylinder by 180°. After turning, the scoop remains closed by the residual torque of the scoop spring. Because the rotation of the bucket is extremely rapid, its shear strength is far greater than the sediment strength, thus cutting cleanly, particularly in soft clays, muds, silts & sands.
After closing, the sample has optimum protection from washout during retrieval by the cylindrical design. This is because, unlike most bottom samplers, the bucket closes with its separation plane aligned in a horizontal rather than in vertical direction. Good samples can be retrieved even when pebbles as large as 2 to 5 cm prevent the bucket from closing properly. And, if you take care to rotate the bucket, you can prevent sample washout completely.
On the deck of your boat, the scoop is quickly removed from the frame by releasing two retaining latches, one at each side of the body. Your sample is then ready for immediate study or transport.