Top 5 Most Popular Plantronics Accessories for Headsets July 2011 1) A10 Direct Cable (66268-03)– The A10 direct connect cable is an economical way to connect H series headsets to certain telephones that have an RJ9 headset jack, such as Nortel, Mitel and NEC. Please contact our sales team at Headsets Direct at 800-914-7996 to determine if your phone can use one. 2) … Continued