Product Info Catalog Tools Power Drill, Bits & Accessories Chuck Key, 0.375 & 0.5-In., 0.25-In. Pilot Shank Chuck Key, 0.375 & 0.5-In., 0.25-In. Pilot Shank Request a Quote UPC: 95456302518 SKU: 373966 Model Number: 30251 Jacobs, 3/8" & 1/2" Chuck Key, 1/4" Pilot Shank.