Whether it is GF9 GS or "GW" GS it is all the same. Neither company "make" it, it is merely repackaged product from another company.
"Green stuff" is simply Blue-yellow kneaditite made by Polymeric Systems Inc. (USA).
They MAKE it and it is available from their dealers in 36" lengths.
My local (listed on the PSI site) sells the 36" for $24 (GW sell 12" for $17).
Pretty much ANYWHERE sells the stuff cheaper than GW.
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