Specifications: INCLUDED: 18 graphite lead refills that have a 5.6 mm diameter, 4B hardness, and 120 mm in height. Don’t fall for competitors with short 90 mm height refills. STORAGE: Each refill is stored in a sturdy reusable plastic case. QUALITY: Our leads are formulated to write uniformly and smoothly for all day writing and breakage resistance. DISPENSER: Each case was designed with consideration for convenience and simplicity resulting in exacting and effortless dispensing. COMPATIBILITY: Our lead works with any brand of 5.6 mm mechanical pencils. Perfect for art, drafting, carpentry and more.