Yes, you need 2 of them for it to work.
By kit I guess that they just mean the content of the box: Adheasive mounting brakate, vice like mounting brakate (with optional spacer), instruction manual, wall charger, main unit and the microphone/headphone unit (and a couple velcro pads to secure the headphone in place))
I love the phone option, I have used it several times (and even though I cannot hear myself talk, i'm told that it is pretty clear). in comming calls are really easy to answer, just press the button on the main unit. If your phone has voice dialing, it can use that (i used it ofr the first time last week and it was much better than pulling off to the side to dial) but regardless it is a million times better than stopping, taking off helmet and then calling!!
~Limits exist only in your minds~
*1987 Yamaha SRX250 (Sold..... For Cash and Neon Beer signs!!)*
*(1991 Honda CBR 600 F2) + (1997 Saab 900s) + $1350 + (my last un-sold Beer sign) = (2006 Honda CBR600f4i)*