Dreadful customer service. I ordered a mask which was compatible with my Phillips CPAP machine and in due course it arrived. Having taken the mask out of its packaging to fit it to my mask holder the circular opening/attachment was too small. Despite several emails on the topic to customer service I am informed that although I paid over £50 for a product which was not fit for purpose, I was not entitled to a refund as it had been taken out of its wrapping. Please tell me how I was to know whether it fit my device if I hadn't taken it out of its wrapper? Completely useless service!!!