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Long time reader first time poster! always find this forum mega helpful
Hows about this one:

I have column headings which are packs, say Cells B1 to D1 are packs 1 to 4

In A2 to A11 are items say nails, screws, bolts, nutts etc

packs (B1 to D1) can have generic or variable items, i.e. pack 1, 2, 3 & 4 can contain item 1 but packs 1 & 3 only contain item 2, pack 4 only contains item 3 and so on...

What I want to do is create a list for each pack in colomn E1 to H1 (Again packs 1 to 4) which lists the contents of the pack without any gaps.

I.E. if pack 3 only contains items 9 & 10 i would like the Column to be G1 (for pack 3)as the pack title and G2 & G3 giving the names of items 9 and 10 respectivley.

I hope this makes sense, the above is a scaled down example I actually have 70 packs and 500 unique items to compile.

Many Thanks for reading
Attached image for ref, Ta