21 Keys: This 21key mechanical numeric keypad features a mechanical key switch structure, offering a linear action for excellent feel and quiet operation. Plug and Play: Simple USB plugandplay connectivity; no drivers required. Compatible with multiple systems, ideal for specialized equipment like banking, finance, and pointofsale systems. LaserEtched Keys: Laseretched characters are durable and resistant to fading, ensuring long key lifespan and comfortable typing. The keys boast a lifespan of 50 million keystrokes, and four antislip feet prevent shaking or accidental falls during use. Features: Spillresistant design. Mechanical linear action switches. Includes Backspace, Esc, Ctrl, Alt, Num Lock, Enter, +, , *, /, and Del keys for efficient data entry. Applications: Perfect for laptop users and ideal for banking, finance, retail POS systems, industrial computers, and various commercial and industrial applications. Supports DOS, Windows 95/98/NT/ME/2000/2003/XP/Vista/7/8/10, Linux, and OS X.