For a plasmid vector to be useful for recombination techniques it must have these important features: 

• Be small in size, ideally less than 10KB in size, so it can integrate easily into the host cell. 
• Possess an origin of replication so that it can replicate autonomously inside host cells. 
• Have multiple cloning sites. 
• Possess an antibiotic resistance gene or selectable marker that helps to identify and eliminate non-transformants and selectively permit the growth of transformants.
• Be capable of inserting a large DNA segment. 
• Feature multiple restriction sites that are unique for different restriction endonucleases, which allows the insertion of target DNA to specific sites on the plasmid. 
• Be capable of functioning under both, prokaryotic and eukaryotic systems.