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OnBuy offers options from third-party sellers ranging from ~£15.79 to £17.99. Where to Buy In-Store (High Street) eBay UK has numerous listings, including multi-packs with
Amazon UK features various sellers with prices typically between £14.20 and £14.89, including "Subscribe & Save" options. eBay UK has numerous listings
Pet Drugs Online offers single cans for approximately £11.99 or twin packs for £23.98.