Hazardous chemicals operation; pharmaceutical production; road dangerous goods transport; special equipment inspection and testing. General items: Class I medical device sales; Class II medical device sales; special equipment sales; mechanical equipment sales; electronic and mechanical equipment maintenance (excluding special equipment); rubber product sales; instrument sales; valve and cock sales; hand carts and animal-drawn vehicle sales; special equipment leasing; mechanical equipment leasing; special labor protection product sales; hardware product retail; special equipment repair; experimental analysis instrument sales; food additive sales.