Which sheath size is represented by the color gray?

Which sheath size is represented by the color gray?

• A. 4F
• B. 5F
• C. 6F
• D. 7F

Answer: (B)

In cath lab practice, sheath color coding is a quick way to identify the French size without reading the label. The size is measured in French units (1F ≈ 0.33 mm). In this color scheme, gray is linked to a 5F sheath, meaning an outer diameter of about 1.67 mm. A 5F sheath is commonly used for diagnostic catheters and radial access because it offers a balance between minimizing vascular trauma and providing enough lumen for standard devices. Always double-check the packaging label, since color coding can vary by brand, but in this context gray identifies 5F.

In cath lab practice, sheath color coding is a quick way to identify the French size without reading the label. The size is measured in French units (1F ≈ 0.33 mm). In this color scheme, gray is linked to a 5F sheath, meaning an outer diameter of about 1.67 mm. A 5F sheath is commonly used for diagnostic catheters and radial access because it offers a balance between minimizing vascular trauma and providing enough lumen for standard devices. Always double-check the packaging label, since color coding can vary by brand, but in this context gray identifies 5F.