Big Gator Tools BGT V-drill 2 Pack V-drillguides W/25 SAE (Standard) Hole Sizes 1/8" - 1/2" Made in USA, Portable, pocket-sized,Prevents drill bit wander Round stock hole alignment marks on one side Special nickel alloyed steel heat treated for durability Non-plated material with light oil coating to prevent rust Centers the holes on pipes, dowels & outside corners