航海装备板块11月20日跌1.93%，中科海讯领跌，主力资金净流出11.88亿元

Group 1 - The marine equipment sector experienced a decline of 1.93% on November 20, with Zhongke Haixun leading the drop [1] - The Shanghai Composite Index closed at 3931.05, down 0.4%, while the Shenzhen Component Index closed at 12980.82, down 0.76% [1] Group 2 - The marine equipment sector saw a net outflow of 1.188 billion yuan from main funds, while retail investors contributed a net inflow of 1.049 billion yuan [2] - Detailed fund flow data indicates that Zhongke Haixun had a main fund net outflow of 20.89 million yuan, with retail inflows of 13.26 million yuan [2] - Other companies in the sector, such as Guorui Technology and China Shipbuilding, also reported significant main fund outflows, with Guorui Technology seeing a net outflow of 46.38 million yuan [2]