Question

What is not an official collar shape?

Answer 1

 It is a shirt collar wich has only  a short (1-2 cm) standing band around the neck, with holes to fasten a detachable collar using shirt studs. Tunisian collar. A "T" shaped collar with a vertical button placket going up to mid-chest.
Generally the collar is of 1cm but some it may exceed to 2cm

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