Product Description: The world's thinnest brush - Estimated 1777 0.01mm ultra-thin and tapered toothbrush bristles Specially designed to massage and care for weakened gums with 3,400 soft and rich brush hairs. Kent, which has been the 'world's best brush maker' since the 18th century, is one of the oldest established companies in the UK. Founded in 1777, Kent is a leader in brush manufacturing history and is a company recognized for its excellence in product quality, to the point that it was granted a Royal Warrant for 9 years after George III.