By the look of it Calders is now produced by Carlsberg-Tetley. Here is some background info taken from their website:
And finally, the Calder's Family. Calder's Beers take their name from John Calder, a 19th Century Scottish pioneer in the field of brewing. Today, there are seven beers in the Calder's family ' Calder's Premium Cream Beer, a premium nitrokeg ale which is available nationally in both the On Trade and Take Home, and six other Scottish style beers which are available in the On Trade in Scotland and North East England.
http://www.carlsbergtetley.co.uk/great_brands/logo
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