Shop by Size (metric)

Shop spiral ducting and fittings by diameter. Our metric sizes run from 80mm right up to 1000mm across 23 size pages, and each page gathers everything we stock in that diameter — 90° curved boots, 45° pipe saddles, reducers and 90° pressed saddles and more — so a complete run can be put together from parts that are guaranteed to match.

Alpha Air Ventilation Supplies is a Leicester-based supplier of commercial and industrial ventilation equipment. Stocked items ordered before 3pm are dispatched for next-working-day delivery, and UK delivery is free on orders over £400 ex VAT.

Prefer to work in inches? The same products are organised under our imperial size categories — 100mm is about 4 inch, 150mm about 6 inch, and so on up to 40 inch.