Battery current supply

Primary (disposable)
Typical capacity (mAh) Nominal voltage

Alkaline-----------------565--------------9V
Zinc–carbon------------400--------------9V
Lithium-----------------1200-------------9.6V

Rechargeables
NiCd ------------------120--------------7.2- 8.4 (some)
NiMH ------------------175-300----------7.2- 8.4 9.6
Lithium-ion polymer-----520---------------7.3-

Wal-warts are used to run equipment and have a built in reserve capacity to run the electronics and charging battery(s) at the same time.
9 volt batteries can produce several amps , but just for a fraction of a second.
finding out what the capacity of a battery is can only be found by the company data sheets.
The more load on the battery the shorter useful life of the battery.
Just remember this some wall-warts are AC in and AC out, while others are AC in and DC out

Okay, what am I missing? What does the wall wart have to do with the battery? Are you asking the capacity of the battery or ultimate short circuit current capability?

Set up: I'm holding a 9-volt battery replacement ("wall wart") in my hand. Besides the output voltage, the label says 200 mA.

Question: I'm now holding a 9-volt battery in my hand, the rectangular kind you can buy anywhere. How much current is it good for?