Cheapest that this has been on Amazon as per the 3 Camels
Double wall 12 oz (~ 350ml) glass. Generally for around $30-$40 elsewhere.
Keep hot drinks hot and cold drinks cold
Feature two walls of borosilicate glass
Creating a highly effective layer of insulation
Silicone valve at base allows for changes in pressure
Perfect for serving ice cream and soups
Edit #2 (04/10/20):
Now back in stock
amazon
also $24 for 450ml