Features: portable NMP822A practice keyer with CR2032 battery operation features audibledly rhythm feedback and LED lighting, offering cable convenient for CW enthusiasts Slimmer than a standard eraser, this keyer integrates vertical straight key, paddled key, and half automatic mode while maintaining exceptional portability for keyboards case or pockets. Ideal for both novice Morse code learners needing visual/auditory rhythm guidance and experienced operators to refines their CW style during mobile practice. Perfect for skill refinement in travel, office, or outdoor setting,its space efficient design fit seamlessly besides keyboards without disrupting workflows or storage. Green LED pulses synchronized with customizable keying speed, transforming Morse practice into immersive experience that bridged technical precisions and rhythmic. Specifications: Part Name: CW Trainer Color: Photo color Material: ABS Size：about 6x3cm/2.36x1.18in Package Includes: 1PC Vband keyer connector note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.