Hello,
In a Loop, the "normal" tunnel is used to pass any kind of data from the outside to the inside of the Loop as is. Each iteration will see the same data.
The indexing feature is only valid for arrays.
When used on inputs, the loop count of the Loop is set to the array size (for For Loop) and each iteration returns, inside the Loop, a single element of the array at a time.
When used on outputs, an array is generated at the output by concatenating the element inside the Loop at each iteration.
Cédric | NI Belgium