FlexiFit 431 Full Face Under-Chin CPAP Mask
FlexiFit 431 Full Face Under-Chin CPAP MaskFlexiFit 431 Full Face Under-Chin CPAP MaskFlexiFit 431 Full Face Under-Chin CPAP Mask

FlexiFit 431 Full Face Under-Chin CPAP Mask

PRICE:  £109.00(plus 20% VAT if applicable)
Most products qualify for Zero Rate VAT Relief which will be shown at checkout if applicable.
Please read the VAT Declaration below.

Part Number:  HC431U
Brand:  Fisher & Paykel



In stock

  (1 Review)

Fisher & Paykel

This is a longstanding popular under-the-chin Full Face Mask by Fisher & Paykel.

This FlexiFit 431 Full Face Mask by Fisher & Paykel is still a popular longstanding mask due to its robust design and 'under-the-chin' support.

Hope2Sleep's Observations:-

  • A positive for people looking for a different mask is that all 3 cushion sizes are included in the pack.
  • There are not so many masks with under-the-chin supports, yet this type of mask can help many people who have receding jaws and find that their mouth falls open during sleep and the chin can fall out of the bottom of masks.   In fact this particular mask came to the rescue of Kath Hope, the founder of Hope2Sleep, many years ago when she was struggling with this problem!
  • The Glider Strap across the front of the mask helps keep the mask sealed when turning the head from side to side.
  • The headgear can also be adjusted on the top of the head, which is always a good feature for added fit and stability.  Additionally, there is a quick-release cord for 'quickly' taking off the mask.

Fisher & Paykel say:-

Incorporating the FlexiFit technology with auto-contouring properties, the FlexiFit 431 Full Face Mask comes with an under-the-chin fit and highly contoured silicone seal for maximum comfort and stability.

FlexiFit 431 Mask Features

The FlexiFit 431 pack includes all 3 sizes of mask cushions - small, medium and large, and once the correct size is found replacement cushions can be purchased in that size to save re-purchasing the full mask often.

Important Tip

Due to the chin support on these mask cushions, if a comfort Silent Night Liner is required with this mask then it is best to select the size Large liner.



Average Rating (1 Review):  
Write a Review and share your opinions!

An answer to my struggles
Thursday, 1 October 2020  | 

I went through lots of masks but had the annoying problem of my mouth falling out of the masks so was pleased to find this one that secures my chin. Finally I have a mask that stays in place all night without waking me up.


This review has not been appraised.


So pleased to hear this and is a mask we often recommend for your specific problem.


We try our best to ship all orders received by us Monday-Friday on the same working day if received before 12 noon, and more often than not orders processed before 3 pm will be despatched the same day whenever possible.  Weekend or UK bank holiday orders are sent out the next working day.  An automated email is sent when products have been despatched so please check your spam box and add us to your safe senders list.  Also, if you do not receive an email confirmation, please check that you have typed the correct email address in your account.

All orders are sent via 1st class mail within the UK.  Masks and some other more expensive products are always sent via 'signed for' insured delivery and cannot be left in 'safe' places, but there is the option for an alternative shipping address when processing the orders.   International orders are sent via tracked Airmail, and whilst we're happy to ship internationally, we cannot be held responsible for any charges that may be added in your own country.

Delivery charges are worked out automatically by weight and you can clearly see the delivery charges before purchase.  On the rare occasion delivery charges are miscalculated by the website, a refund will be sent, as it is not our policy to make money on postage charges and neither do we add the cost of delivery into the price and offer so-called  'free delivery' like some sites and Ebay pressurise sellers to do!

Wherever possible with larger parcels, we try to re-use boxes to keep shipping costs down and protect the environment.

If a product is out of stock and the order contains multiple items, the 'in stock' items will be sent immediately and further items will follow upon arrival with no further postage charges incurred.  


Masks, CPAP machines and and most other products are exempt from a refund or exchange unless faulty due to health and hygiene issues (as stated in our 'Terms and Conditions'), and in particular due to the risk of cross contamination as they cannot be re-sold. The Consumer Contracts Regulations 28.(3)(a) confirms exemption as follows:-  "exemption in the case of a contract for the supply of sealed goods which are not suitable for return due to health protection or hygiene reasons, if they become unsealed after delivery."

Unopened (sealed) products in their original packing can be returned within 14 days for a refund of the product cost, but the purchaser is to pay the return postage, and we would advise retaining proof of postage.  This excludes any faulty goods, for which postage will be reimbursed.  A full refund for the price of the product will be issued when received by us, less the original postage charges when the order was sent to you.



Most of the products we sell are eligible for Zero Rated VAT in the UK and Europe, and in order to qualify, you should meet the criteria for the following HMRC VAT Declaration:-

  1. You or the person you are purchasing on behalf of have "a condition which the medical profession treats as a chronic sickness," (sleep apnoea and sleep disordered breathing, which require therapy, are such conditions).
  2. "The goods or services are for the personal or domestic use of the customer."

We cannot advise on individual cases, but more information can be found on HMRC’s website under notice 701/7 on the following link

If you are purchasing on behalf of someone else who meets the above criteria, you must provide their name and address, and you will be prompted of this during the checkout process.

Customers living outside of Europe do not pay UK VAT charges, so please leave the the 'zero rate eligibility' box ticked.  However, we cannot be held responsible for any additional costs incurred when the products reach your own country.

If you are purchasing with the intention of re-selling any products, you are liable to pay VAT on all products so you must untick the 'zero rate eligibility' box which will add VAT to your order.

Any products that our not eligible for zero rate VAT, will not display the VAT Declaration, and VAT will be added at checkout.