Weber part # 61450.91; outer diameter: 7.5mm, inner dia.: 3mm, the lowest set of holes (4 holes, each one is 2.5mm) are 7mm from the bottom of the tube however the tube reduces is outer dia. to 6mm directly above the holes for about 12mm from where the holes start. Next set of holes are 19mm from the bottom of the tube and are 1mm times 4. The next set of holes are 28mm from the bottom and are 8 in number and are 1mm each. Overall length is 50mm. Got all that? Now go grab a beer! :wacko: