Flat kit help

What do you consider a "flat kit?"  

Tire patch kit?
Replacement tube?
Tire levers?
CO2 cartridges?

Multiples of the above?  

What about ID?

Other tools?  

For racing?  For training?  Both?  

For a while, I had extra bottle cages on my tri-bike and used a bottle as my tool kit.  

Assuming you had something before, and now you're seat is lower and there isn't enough space?  Smaller bag?  The underseat bag on my tri bike is about 1/3 the size of what I have on my road bike, but since it's primarily for races, it's OK.  

Pics of your setup?  

Good questions. Replacement tube(s), tire levers, CO2 and the little inflater thing. No puncture kit.

I wear a Road ID, so no need for that space. I don't carry other tools. This is on my tri bike, so it's primarily for racing, but also for some training (all of my riding for the next two months will be on this bike).

My seat went up and it went forward. I used to have just enough space for my saddle bag to hook on the seat rails, but now it's too far forward. The saddle bag is already pretty small.

The only pics I've got are from my fit last week, and I doubt they'll show a lot. Let me know if you want to see it, though, and I'll attach the report.

I like this idea. I had ordered the X-Lab Delta 105 with multi-strike repair holder. I liked the idea of having my tube, levers, CO2 back there, and I could put my saddle bag with phone in the cage (or, if a longer ride, another bottle). Unfortunately, my seat is so far forward that there is not enough clearance between the seat post and the bottom of the cage. The pocket might be a good solution. Thanks.

I had all my spare kit needs in my VR frame bottle.