Self inflating mattress, slow leak, fine for kids (Broomhill S10)

Large single self- inflating mattress and carry bag. The valve doesn’t seem to reliably seal fully any more, sometimes it’s fine all night if you get it closed perfectly, more often it gradually deflates through the night, more so the heavier the person. Kids have slept on it without any problems. Hope someone might be able to make use of it or maybe replace the valve??

Collection from Crookes Crosspool area S10.

       
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