M-D Building Products 9415 Premium Low Dome Top Threshold 312L, 36 Inches, Brite Gold All season protection against drafts, moisture, dust and insects Heavy duty aluminum and vinyl for long lasting seal and durability Vinyl strips on base provide a weathertight seal against floor Seals gaps up to 5/8 inch high 3-1/2-inches wide by 5/8-inch high by 36 inches long