This is a classic vintage prismatic glass lamp shade, often referred to as Holophane style due to its characteristic ribbed design. The shade features vertical exterior ridges that are designed to diffuse light evenly, creating a soft and functional glow. Its flared bowl shape is timeless, making it an excellent replacement piece for antique pendant lights, industrial sconces, or schoolhouse-style fixtures. The glass has a slight greenish tint common in older pressed glass, suggesting a mid-century or earlier manufacture. The top opening is designed for a standard 2.25-inch fitter. This piece is ideal for restorers of vintage lighting or those looking to add a touch of industrial or mid-century charm to their home decor. The thick, heavy-duty glass construction ensures durability and reflects the high manufacturing standards of the era. It is in excellent vintage condition with no visible chips or cracks.