strict liability

Bob is shopping in Carl’s Hardware Store when a nail gun in use by Dan, one of Carl’s employees, fires without warning and hits Bob in the leg. Carl checks the gun and discovers that it was assembled improperly. Bob files a suit against Eagle Tools, Inc., the manufacturer of the gun, for product liability, on the ground of strict liability. What are the elements for an action based on strict liability? In whose favor is the court likely to rule and why?