Refractory Ceramic Furnace Muffle from Mexico
High-alumina ceramic muffle protecting furnace heating elements from process atmosphere. Named example in HTS 6903.90.00 for refractory muffles used in industrial heat treatment. Fired ceramic construction per Chapter 69 standards.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Furnace OEM end-user letter prevents parts classification; verify no electrical function
• Common error: complete muffles with embedded heaters go to Chapter 85