Why this ducting earns its place
This Combisteel converter handles the largest junction in a typical kitchen extraction system: stepping from a 400 × 400 mm square main trunk down to a 450 mm round outlet for high-capacity branch runs. The oversized round diameter means very low air resistance, letting extraction systems move serious volumes of air with minimal noise and pressure drop—critical when you're serving a large kitchen with multiple cooking stations pulling simultaneously.
The converter itself is a solid 400 × 400 × 280 mm casting, built to commercial standards and designed for permanent installation. Whether you're building a new high-end kitchen, retrofitting a commercial catering space, or speccing an extraction system for a large hotel or restaurant group, this adapter ensures the transition from trunk to branch happens smoothly and efficiently. The larger diameter means a lower velocity of air movement—quieter operation and longer equipment life.
Professionally installed with proper foil tape sealing at inlet and outlet, this converter becomes invisible in your extraction system: no leaks, no turbulence, no noise penalties. It's the kind of component that contractors specify knowing it'll last for years, handle the load, and never become a maintenance headache or a source of energy waste.
