It was during the Vietnam war and I was in Japan on a brief shore leave from a U.S Navy ship when in an electronics store I saw a device I'd never seen before; a hand-held audio cassette recorder. I immediately saw the possibilities and they intrigued me, so I bought two.
As soon as I could I began recording an aural letter to my wife. I asked about our daughter, asked what was happening at home, all the small talk that usually goes in a written letter. But it soon felt as if I was speaking directly to her so I told her how in my mind's eye I could see her beautiful smile, her lovely round breasts, her perky nipples and her bountiful black pussy hair. I told her that the thought of her made my cock stiff and throbbing and that as soon as I finish the recording I intended to jack off.
Since I was the ship's Captain I had the privacy to speak into the recorder and best of all the privacy to masturbate whenever I wanted-which was often!
The tape and her recorder were in the mail the next day.
At sea a couple weeks later a helicopter delivered our mail. I was excited to see a small package that I knew must be a tape from my wife. Everything was routine on the ship so I got undressed and in my bunk. I pressed the play button and heard her say 'My love, knowing that you were thinking of me and stroking your hard cock made me so hot and wet!' There was a moment of silence and then I heard the wonderful, familiar sound of her vibrator. I could almost see her on the bed with her legs spread and the vibrator on her swollen clit. I heard her say 'Oh, it feels so good! Do you have your cock in your hand?-I know you do!' I was indeed masturbating vigorously! Moments later I heard her almost scream 'Oh, oh, god I'm cumming, I'm cumming!' We had wonderfully explosive orgasms in unison.
The next night I covered my cock with Vaseline and pressed the record button hoping she would hear the 'squishy' sound of my fist going up and down my very hard cock-a sound I knew would turn her on. I told her how much I loved to hear her cum and how much I loved to jack off with her. There were grunts and 'Oh yes, yes I do so love to jack off with you! I'm cumming' I said as the hot cum squirted onto my chest.
These hot exchanges continued for the rest of my deployment and brought joy to the otherwise stressful months. And to this day I have an interest in technology and a fascination-one could even say, an obsession, with mutual masturbation; I wish I could do it all day, every day.