hey whats the diffrence in bells

1L and just 1 and also thre rest 4a and just 4 i belive 1 is amercian tuned
but i noticed not all bells can be either or only certain bells can either be A or a non Amercian but i seen people having like 1L .1 AND A 2 BELL COMBO
1 L and 1? what the diffrence
a american k3la would contain which bells?
1L 2 AND 4A? AM I correct
if anyone wants to just aim me the answer lol feel free im always on
iceblu121 on aim
thanks guys!
might be upgrading and buyin my self a k3 with the custom mounting kit from curt .s