SHARP EL-520D TWIN POWER SCIENTIFIC CALCULATOR in working condition The Vintage Sharp EL-520d Programmable Scientific Calculator is a handheld device with regular key size, powered by batteries, and is designed with a case for easy storage and portability. This calculator is a model from Taiwan that is considered vintage, making it a unique and nostalgic piece for collectors or enthusiasts of vintage electronics. The Sharp brand is known for its quality and durability, ensuring that this calculator is not only a functional tool but also a valuable piece for anyone interested in retro technology.