Since 1930 the Petersen grab has been used in fresh water for collecting macroscopic fauna in sand, gravel, marl, clay or clay combinations. If used in salt water, it must be painted for protection. Since it has been widely used over 6 decades, it is ideal for comparing samples with data collected previously by a Petersen grab. Vent holes permit water to flow through while the grab is being lowered, minimizing diagonal movement as well as reducing the frontal shock wave generated by descent. Jaws close clamshell fashion. We include a safety-pin to prevent the scoops from closing to help prevent injury. The bayonet-style trip mechanism is designed to release only when the sampler is on the bottom and the cable is slack. A deliberately heavy device for biting deep into hard bottoms. Can hold up to 8 removable weights. Operation requires winch and crane due to the working weight. Ship wt: 115 lbs.
• Materials: Zinc-plated heavy steel
• Weight: 34 kg (75 lbs.), With extra weights: 42 kg (93 lb.)
• Volume: 9890 mL
• Sample area: 305 x 305 mm (12 x 12”)
• Includes: Shipping crate, 4 weights
• Extra weights available separately, pack of 2, 9 lbs each