What started out as a lark is now a learning experience. Curses to education!!!
I did not know that there were Schick Kronas with plastic tips. All three of mine are metal-tipped.
Obviously, the only solution is for me to buy every existing DE razor in the world, spend the rest of my life holed up in a cabin in Montana, and categorize all the differences (with proofing by Messrs. Krumholz, Guido, and Eye).
Now, where did I put that winning lootery ticket . . . .
Just so you can see the difference.