Brand & Labeling:

 * The shirts are labeled with "Calvin Klein" and "Lorenzo Benzoni." The labels also feature the "ck" logo, which is embroidered on the pocket of each shirt.

 * The prominent display of the "Lorenzo Benzoni" brand tag alongside the "Calvin Klein" name suggests that this might not be an official Calvin Klein product. Calvin Klein is a well-known international designer brand, and its official merchandise is typically sold through its own stores or authorized retailers. The presence of another brand name on the label, especially one that is not a recognized collaborator with Calvin Klein, indicates that these are likely imitation or counterfeit products.

Features:

 * Material: The shirts appear to be made of cotton, based on the description in the user's request and the likely feel of the fabric.

 * Design: Each shirt is a solid color with a button-down collar and a single chest pocket on the left side.

 * Logo: The "ck" logo is embroidered in black on the chest pocket of each shirt.

 * Sleeves: Long-sleeve with buttoned cuffs.

Colors:

The shirts are a pastel color palette, which includes:

 * Light pink

 * Light yellow

 * Light blue

 * Light green