Replace with column header or concatenate?

Hi Folks,

I have a table of data with a reference in column A, the column headings are frequencies. The result is what i am looking to achieve, basically concatenate the heading values if there is a "1" in the row? Perhaps there is another way but the Result is what I am looking to achieve. If you could explain the make up of the formula that would be most appreciated.

Sample.JPG
Thanks and stay safe

G

Since you do not have Office 365, you have probably 2 choices: a UDF (requires saving as an .xlsm) or a helper column. Your choice. Please read the yellow banner at the top of the page and attach a small sample sheet.

Lets go with a helper column if possible.

Please try at
AB2:AY6
=AA2&REPT(","&B$1,B2)

Z2
=MID(AY2,2,99)

Result, thank you so much :-)