Wild ties 

Men's Green Mi­cro­fi­ber Pi Sym­bol to the 50th De­ci­mal Ma­the­ma­tics Math Nerd/Geek No­velty Tie Neck­tie (Re­gu­lar Length) 

Pi To The 50th De­ci­mal Green Mi­cro­fi­ber Ex­tra Long Tie | eBay 

Pi TO THE 50TH DE­CI­MAL MATH GEO­ME­TRY NERD TEA­CHER Wild Ties Silk Neck­tie NEW! | eBay 

Wildties 

Green Mi­cro­fi­ber Pi To The 50th De­ci­mal Tie | Ties.com 

Wild ties 

Pi TO THE 50TH DE­CI­MAL MATH GEO­ME­TRY NERD TEA­CHER Wild Ties Mi­cro­fi­ber Neck­tie | eBay