Help With Internal Bike Carrier

[LGee48]

We recently bought a S-Max and have bought the activity kit :

Images may vary

Activity kit short aluminium bar

minimise

for third row for vehicles with seats only, from 2006 onwards

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I want to know if the Short Bar you need two? one for the front and one for the back?

Also can anyone offer any tips on fitting we have yet to do this, we are having a tow bar fitted and will also be using out thule carrier that goes on the tow bar but when its just one bike we want to use the internal mounting just the intructions you get with it are poor to say the least.