Ebanlan via eBay continues to offer this Full Face Snorkel Mask in Blue, Black, or Rose Red for $30.99 with free shipping. That's tied with our mention from a week ago and $9 under the lowest total price we could find for a similar mask, outside other eBay merchants. It features 180° viewing, a breathing tube, drain valve, and compatibility with a GoPro camera. It's available in sizes S/M and L/XL.
Of note, this item ships from Hong Kong and may take two to four weeks to arrive. It's also available in Rose Red size L/XL for $29.49.