This tube features a self-sharpening tip that cuts great looking cores and outlasts common replaceable tips eight to one. Works best in soft, moist soils. Sample core measures 0.688 inches in diameter. Length is 12 inches. Hardened cutting tip. All metal parts nickel-plated to protect against rust and wear. Easily cleaned with the JMC Special Cleaner tool. Compatible with all JMC Backsaver, Conventional, Collapsible, and "T" Handles.