SSI Marine Invertebrate Ecology Options:Classroom and Pool comes with O-Ring

comes with O-Ring

Halcyon V-weight pouch is designed to provide additional ballast to double cylinder divers and fits securely between the two cylinders and the backplate

Elastic gussets under the armpits

XDEEP DIR harness with stainless steel backplate

SSI Marine Invertebrate Ecology Options:Classroom and Pool comes with O-RingSSI Marine Invertebrate Ecology The underwater world is full of incredible creatures that often go unnoticed. From colourful sea stars and delicate shrimp to fascinating octopus, crabs and corals, marine invertebrates make up some of the most diverse and important life forms in our oceans. The SSI Marine Invertebrate Ecology Speciality introduces you to these amazing animals, helping you understand their biology, behaviour, adaptations and the vital