Use Quidco and the free delivery code (bhsnectar) to get these for £9.30.
As per the BHS website:
4 Pack Recovery Pillows - These Recovery Pilllows contain spiral fibres that bounce back with enhanced shape rententiveness, maintaining their shape night after night. This product is fully washable and has new non allergenic properties including anti dust-mite, anti bacterial and anti fungal
Spiral fibres that bounce back with enhanced shape rententiveness
Fully washable at 40 degrees (wool cycle)
Filling: 100% polyester hollowfibre
Cover: 65% Polyester 35% Cotton
Pillow 74cm x 48cm (approx.)