Men's Green Microfiber Pi Symbol to the 50th Decimal Mathematics Math Nerd/Geek Novelty Tie Necktie This tie is for the nerds. Featured within this grand necktie is the great and almighty symbol of Pi Regular and extra long length available! Select size from dropdown menu for exact dimensions. Made of Microfiber Neck Size: 14.0'' - 19.0'' SATISFACTION GUARANTEED - Your satisfaction is 100% guaranteed. We offer a 30-day money-back guarantee and phone, email, and live chat support are available on our website!