Shorted load output and blew FET on BMS

Hello....

I have a 5S 20A BMS that is supposed to have short ckt protection....I shorted the load yesterday (+ to -) only to blow the two FETs located on the low side of the B- ....Can someone tell me how short ckt load protection is done on the BMS? Is it done on the high side or low side? How come I don't see any PPTC (resettable fuses) on these as many say they are recoverable after you remove the load?

Thanks

My guess is that the Battery IR is really low so the high current destroyed the Fets before the MC could react to it (likely cheap BMS).
"Resettable" means that the Fets simply turn off and then turn back on when the short is removed, so no fuse needed.
You could of course add an additional fuse for extra safety