DECORATIVE HECKLER & KOCH, INC. HK-91-A2 ACRYLIC BLOCK DISPLAY. Acrylic block features: Thick solid free-standing acrylic block for desk, table top or shelves. Diamond cut sides provide a sharp image from any angle Hand polished for a crystal clear finish. Measures 4.5″ x 2.5″ x 1. Acrylic block stored in garage since the 80’s in box marked HK stuff. Acrylic block in pristine, immaculate condition, I do not recall. This acrylic is now a collectable item for HK enthusiast. Acrylic is a transparent plastic material with outstanding strength, stiffness, and optical clarity. Acrylic blocks exhibits glass like qualities, clarity, brilliance and transparency but at half the weight and many times the impact resistance of glass. Not responsible for uninsured items. We have lots of great items!