Often bought, as where Sakae ninja, as a fairly cheap, durable and fashionable 24T chaining in the early 90's when 26T was the common granny ring found on chainsets. Stainless Steel as well.
As for the spacer differences, well they should have come with them in the plastic carton.
No idea what they did in the mid 90's and their restyling and cut off teeth. But it was the 24T granny that made 'em popular in the early 90's