Easy Loading. User-friendly double-wall clamshell design with a large 5-inch outer diameter center-biased media bay, spring-loaded label roll holder, top-of-form sensing by gap, black mark, or notch, includes head-open sensor Durable. High-quality double-walled clamshell design Fast Print Speed. Up to 5-inch outer diameter rolls of direct thermal labels and can print crisp, clear barcodes, graphics and text at up to 6-inches per second