hello and thank you in advance for any help given.

i have a round above ground pool with no labels or literature. i want to purchase a liner how ever the pool is not assembled. i have 15 post and 15 toprails toprails messure 50.5 inches each. Can anyone tell me the size? i think its 21 but previous owner thinks 24 . i dont wanna buy the wrong liner.


thanks again
Jim