Many (if not all) of the Plasctuct kits show two versions of the same kit when doing a search on their website. One is always a little cheaper than the other.
One is listed as KIT 1017. The other is listed 1017-KIT. I wonder if the lower price is kit form and the other is assembled from the kit. Their website is lacking in the detail department.
The Plastruct catalog is sometimes a bit chaotic maybe because their origin was not scale model railroading but rather architectural models, so the scales don’t always match up with model train scales. And because prototype stuff comes in a variety of sizes, it might not be helpful for Plastruct to try to attach a scale to something if in fact the important information is the size of the model and let the purchaser decide based on their knowledge of the prototype which size they want
Going to the slightly more helpful Walthers catalog, kit 1017 propane storage tank is listed as 1 1/2" by 5" tall Walthers lists it with HO
Kit 3017 is propane tank 9" tall by 2 1/2" diameter. Walthers has it in their O scale section
I suppose we could think of them as being HO to S scale and S to O scale although I have not sized propane tanks lately
And the prices are different accordingly. Both by the way are out of stock and need to be special ordered.
You missed the details. Both 1017 kits on the Plastruct website are HO, and both 3017 kits are O scale. Only one of each scale is listed in their catalog. It is when you go to order direct that you find both.
They are all in stock direct from Plastruct. While I have not pulled the trigger I have put them in the cart and started the checkout to see if I got an error message and did not.