Sir, We are writing to make you aware of an inaccuracy in your Supplier Spotlight on Challs (8 January).

The article claims Buster, Challs International's plughole cleaner brand, is 'the biggest plughole unblocker in the country", with value sales of £4.3m.

In fact, market leader in the drain category is Mr Muscle with its Sink & Drain Gel and Active Foamer products. These two products generate annual value sales of £12.9m representing 55% of the category and continue to grow market share and volume.

Astrid Diester, group product manager Household Care, SC Johnson.