Round shutters and square shutters are pre-fabricated formwork panels used to shape concrete columns during casting. They are made of steel with a supporting frame, designed to hold the concrete in the desired shape until it sets. Square shutters are used for rectangular or square columns, providing straight edges and uniform surfaces. They consist of flat panels with stiffening members and are assembled around the column using tie rods, clamps, and props.

Round shutters are used for circular columns and are curved panels that form the circular profile. They are typically made of curved steel with a rigid frame to resist the lateral pressure of wet concrete. Both types of shutters transfer the load of fresh concrete to props and supporting structures, keeping the panels aligned, stable, and plumb. They are reusable, adjustable, and essential for producing accurate, smooth, and durable columns in building construction.