Form C: with external thread, flattened ball, smooth.
Form D: with external thread, flattened ball, with POM insert.
Form F: with external thread, flattened ball, diamond grip.
Form M: with external thread, flattened ball, with carbide insert.
Form G: press fit, flattened ball, smooth.
Form H: press fit, flattened ball, with POM insert.
Form J: press fit, flattened ball, diamond grip.
Form K: press fit, flattened ball, with carbide insert.