Usage:

1. Determine sampling place.

2. Stretch grab bucket, put support rob into buckle and pull rope closer, then the grab bucket will stay open condition.

3. Put the stretched grab bucket into river slowly, release rope while contacting the river bottom, then the support rod will detach with buckle under gravity effect.

4. Lift rope by strength and the stretched grab bucket will close slowly. Lastly the bottom sediment will be collected inside grab bucket while closing.