Pica BIG-Dry Stonemason 10H Refill Leads, 12PK 12 high-quality leads housed in a convenient plastic storage box designed with a two-piece wing lid for easy access. These rectangular leads measure 2 x 5mm in profile and are 150mm long, crafted from graphite with a special 10H hardness. They are ly suited for marking on dry and rough surfaces such as brickwork, stone, and concrete, making them an essential tool for stonemasons and construction professionals who require precision and durability in their marking tools. Model Number: 6055