8 x Crossaction heads for £14.10 with the £3 voucher available now (just click the box below the price where it says voucher). This is valid until the end of the month.
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Looking at CamelCamelCamel, it's the cheapest price you usually get, but with the voucher it's obviously a bargain! Great to go with the cheap Oral-B electric toothbrushes on sale everywhere.