The term HD 5x5 Closure refers to a specific type of hairpiece used in creating protective and versatile hairstyles, particularly sew-in weaves.

Here is a detailed description.

An HD 5x5 Closure is a small, rectangular piece of lacewith indi vidual hair strands hand-tied into it. It is designed to be sewn onto a braided base to cover the top of the head, creating a natural-looking part and hairline, and allowing the wearer's natural hair to remain protected underneath.

The name breaks down as:
HD: Stands for High Definition. This refers to the extremely fine, thin, and transparent lace material used. This transparency allows it to blend seamlessly with various scalp tones, making the hairpiece virtually undetectable.
5x5: Refers to the size of the piece: 5 inches by 5 inches (approximately 12.7 cm x 12.7 cm). This is one of the most popular and versatile sizes.