Razor wire is mainly divided into two model families: BTO and CBT. BTO models, often called short-blade type, have a single-coil design that expands into large diamond-shaped grids. Common BTO specifications include BTO‑10, BTO‑12, BTO‑15, BTO‑18, BTO‑22, BTO‑28, and BTO‑30. The numbers indicate blade length in millimeters, ranging from 10 mm up to 30 mm, while the blade width varies between 13 mm and 18 mm, and spacing from 25 mm to 46 mm. A typical BTO blade is about 0.5 mm thick with a core wire of 2.5 mm. CBT models, known as long-blade or large-spike type, produce straight, sharp protrusions. Examples are CBT‑60 and CBT‑65, with blade lengths of 60‑65 mm, width around 21‑32 mm, spacing of 100 mm, and blade thickness of 0.6 mm. For any razor wire, the spiral coil diameter (when compressed) ranges from 450 mm to 1000 mm. Smaller diameters like 450‑600 mm are used on fence tops, while larger ones up to 1000 mm work best for open boundaries. Material options include hot-dipped galvanized steel for general use and stainless steel 304 for corrosive coastal areas. PVC coating adds extra weather resistance and color choice.