Which is why, if you've got things in your Sunlu shopping cart, you might want to wait a week.

The company's 12th Anniversary sale, "Everyday is Prime Day", will include different stages of offers throughout July. And it won't just be about filaments receiving the discount treatment – the anniversary will also include the pre-sale of the AMS Heater going live on July 6.

As for the mystery gift (worth $10)? It's a "Limited offer. First come, first served." Who'll be the lucky makers getting the surprise? And what will it be? We'll have to wait and see.