This is the last weekend of Fenris Games‘ Summer Sale.
From their announcement:
Just a reminder that there’s less than 36 hours to go on the Fenris Buy 3, Get a 4th Free summer sale. Offer applies to direct sales only, with orders placed at email@example.com.
Just tell us the items you want and provide a valid PayPal address and we’ll issue an invoice, with the cheapest item from every four chosen being free.
Offer applies to everything in our eBay store except OOP miniatures. Last orders have to be in by midnight GMT 25th July to qualify for the discount.