^ They have extra cables in the site or you can retrofit(wire permanently) RJ45 female socket so that you only have to bring Ethernet straight-cable. Just put-on a good cover to the RJ45 jack to protect the live pins. Here are the pin-outs
J1962 Female RJ45 signal
1 nc
2 4 PWM/VPW (+)
3 nc
4 1 chassis gnd
5 1 signal gnd
6 2 CAN hi
7 6 K line
8 nc
9 nc
10 5 PWM/VPW (-)
11 nc
12 nc
13 nc
14 3 CAN lo
15 7 L line
16 8 (+) power
RJ45 Twisted pairs - 2,3 & 4,5
BTW dont use a wall-type RJ45 connector if you dont want your car to look like a house