DOOWIN is China’s leading manufacturer of underwater lift bags, marine salvage bags, and crane test water weight bags, complying with IMCA D016 and LEEA 051. Products include open-bottom, enclosed, and pillow lift bags for diving, salvage, and pipeline buoyancy support. Water weight bags serve crane and lifeboat proof load testing. With 30+ years of experience, DOOWIN serves global clients in diving, marine rescue, oil & energy, and offshore shipping. Products are ISO 9001:2008 certified by SGS, BV, CCS, ABS, and LR. Trusted by major contractors and end-users worldwide.