Of course there was a version sold by Sears which was basically the same thing as Armstrong was part of Danaher by then and would have been the supplier of the Sears Craftsman product when it was made in the United States. I worked in the automotive aftermarket for 11 years and have been in the industry for 35 plus so part numbering is something I'm familiar with. Generally part numbers are supposed to make some kind of sense from an inventory point of view and in recognition. For instance certain groups of products all had the same prefix when we were assigning them so that people knew what type of product it was when it came in a bulk shipment. I would think Sears is a retailer would partially perhaps not care about that since some SKU numbers may have been reused or for that matter it didn't matter to most people when they were putting them away on the shelf. They just went by the stock number and matched them up. Sears did use some thought when assigning model numbers to products as the full model number was what was used to order parts, but the shortened version of that was often the stock number that was used when it was sold, advertised, or to refer to it. For instance I have a 1968 Sears air compressor and the full model number is 106.153680. That is how you order parts for it with the 106 meaning that it was made by Campbell Hausfeld. However in the catalog back then it would just show as a model number 15368. That is what the people on the sales floor refer to it as and likely how it was kept in inventory.
Of course there was a version sold by Sears which was basically the same thing as Armstrong was part of Danaher by then and would have been the supplier of the Sears Craftsman product when it was made in the United States.
I worked in the automotive aftermarket for 11 years and have been in the industry for 35 plus so part numbering is something I'm familiar with. Generally part numbers are supposed to make some kind of sense from an inventory point of view and in recognition. For instance certain groups of products all had the same prefix when we were assigning them so that people knew what type of product it was when it came in a bulk shipment.
I would think Sears is a retailer would partially perhaps not care about that since some SKU numbers may have been reused or for that matter it didn't matter to most people when they were putting them away on the shelf. They just went by the stock number and matched them up.
Sears did use some thought when assigning model numbers to products as the full model number was what was used to order parts, but the shortened version of that was often the stock number that was used when it was sold, advertised, or to refer to it. For instance I have a 1968 Sears air compressor and the full model number is 106.153680. That is how you order parts for it with the 106 meaning that it was made by Campbell Hausfeld. However in the catalog back then it would just show as a model number 15368. That is what the people on the sales floor refer to it as and likely how it was kept in inventory.