This is a Barcelona-style 2-in-1 four cup teapot and infuser from La Cafetière. Its stainless steel filter has a fine mesh which retains flavour and prevents leaves from leaking into the brew.
It holds up to 1.2L (2 pints, 41 fl oz). Its high-quality ceramic build and grey / white colour scheme makes it durable both practically and in design. It's also available in a 2-cup model.