Mustad Demon Perfect Circle Hooks, Size 4/0, 25 Pack - 39951NP-BN-4/0-25Up Demon perfect in line circle hook. Mustad's Wire Technology And Nor-Tempering Process Means That Hooks Are Lighter And Up To 20% Stronger. UltraPoint Technology Means Sharp, Durable Hook Points That Resist Rolling And Stay Sharper Longer.