China Oilfield Services Limited (COSL) is a solution provider of integrated oilfield services in China. COSL provides four categories of services: drilling services, including rig, module rig and rig management services; well services, including logging, drilling fluids, directional drilling, cementing and liftboat services; marine support and transportation services, offering transportation services of materials, supplies and personnel, and geophysical services, providing the services of seismic and construction survey and seismic data processing. COSL's services cover each phase of oil and gas exploration, development and production. As of December 31, 2008, COSL operated 23 drilling rigs ( of which 20 are jack-up rigs and three are semi-submersibles) , two platform supply vessels, four module rigs and five onshore rigs. The Company also possesses and manages more than 70 supply vessels, four oil tankers, five chemical carriers, eight seismic vessels and four surveying vessels.