Will the 2 different sizes of stretcher blocks on the BCK stretcher Missshape my ball cap?

It will not misshape your cap because a ball cap is pliable, so the only way to influence its form is by how you form the brim/bill of your cap. Fitted caps are manufactured in a round shape. The flatter the brim, the more circular it will be. It will fit more oval the more you curve the brim. Unlike a cowboy hat stretcher, when stretching with the Ball Cap King 59FIFTY Hat Stretcher, you can form your brim any way you want…flat, slightly curved, medium curve, or a country-boy curve.

My cowboy hat stretcher puts a heavy creased line across the back of my caps just above the hatband. will the BCK stretcher do the same thing?

The BCK 59FIFTY Cap Stretcher will not crease a line above the hatband because we put a 3/8” roundover on the top of the stretcher, so it won’t dig into the cap when stretching.