How to choose a battery for a UPS?

Question

Uninterruptable power source

Good afternoon. Tell me how to choose batteries for the UPS. I got a dinosaur from Tripp-lite - Smart int 1400 xl. There are very few descriptions of it online. And I got it without batteries. Can you please tell me which batteries can be purchased for it.
UPS specifications:
Input: 230V - 50/60Hz
1500va 6.5A
Output: 230V 50/60Hz
1400va 940w
Preferably batteries with maximum amp-hour rating to keep the load as long as possible.

Answer 1

Google it.
The first link in the buzz gives a user manual from which you can find out the battery model - BP36V27:
www.manualslib.com/manual/183173/Tripp-Lite-Smartp...
www.datasheetlib.com/datasheet/576835/bp-36v27_tri...
In principle, you can supply a battery with similar characteristics and dimensions.