B5.5's as far as I know came with these as standard though don't count on my word.
The ISOFIX brackets sit just behind the base cushion and allow you to simply click a baby seat base onto it and know that it's correctly fitted and secure - unlike the daft messing about you get with seatbelt-secured versions.
When I went in to my local VW dealership to ask about a retro-fit kit for these I was told point blank that if they weren't fitted as standard there was NO retro-fit kit. That's bull. I told them I'd seen the stuff online so the guy went off to ask the 'technical department' who rang me back on the Monday morning and told me the same - NOT available.
So I found the part numbers online:
8B0 813 545A for the actual bracket (you'll need one bracket per seat - so if you've got two kids or want the option of fitting the car seat on either driver/passenger side you'll need two).
You will also need two special bolts per bracket, part number 8L0 837 453 - this may differ depending on your model - but essentially it's the same bolt?!
Lift up the seat base cushion and take a peek at the back - you should see two pieces of sticky tape covering the necessary holes, remove the tape - all B5's have these - not sure about B4's?
(with seat back removed ...)
To gain enough access to bolt the bracket in place you'll need to remove the backrest for the seat too...
Drop the seat back forward and in between the two seat backs there's a small bracket that covers the two centre pivots for the seat backs. This is fitted with a T30 torx screw which you need to remove.
In an estate it looks like this (bracket and screw removed)...
Remove the seat base by sliding it off the pin at the opposide side of the seat back. Then simply bolt up the bracket as shown - make sure you put it the right way up!
The bolts should be torqued up to 30lb/ft. I used a little thread lock on the bolts too.
Refit the seat back. Do the same on the other side if you're fitting two brackets. Job done.
Total cost - £40.60 (inc VAT) per bracket.
there was none! i didn't know what to do tbh, so i rang the mrs and our arrangement was that, the other car we buy honda crv would be the family car, so we could manage, i was a bit pissed off it didn't have them but thought we'd manage, so bought it anyway, then i found this post 
jobs a good un!
