The 410 piece set is now available from Barnes & Noble, although not much help if you’re not US bound.

The official release date is 26th April, which coincides with the release of the new Star Wars and Carnage sets. 

Official description:

Capture forever the unique style of Batman with this challenging and rewarding LEGO® build-and-display model of the super hero’s distinctive cowl. With transparent bricks to represent the face and a stylish fact plaque attached to the base, the iconic helmet belonging to the protector of GOTHAM CITY will make an eye-catching centerpiece, wherever it is displayed.

The LEGO® DC Batman: Batman Cowl (76182) captures forever the unmistakable style of Batman in a captivating build-and-display model created with adults in mind.
Measuring over 8.5 in. (22 cm) high, 4 in. (10 cm) wide and 4 in. (12 cm) deep, this captivating model provides an attractive conversation piece, whether displayed in your home or workplace.
The collectible LEGO® DC Batman Batman Cowl offers a hands-on, stress-relieving building experience, as 410 LEGO bricks gradually transform into a stunning display model.
This authentic LEGO® brick recreation of the iconic Batman helmet includes transparent pieces to represent the face and a stylish fact plaque attached to a sturdy base.
Indulge your creative construction superpowers. This collectible piece of Batman memorabilia will provide pleasure and satisfaction long after the hands-on work has been completed.
This build-and-display piece is ideal for any model-making enthusiast or adult fan of the Caped Crusader. It makes a great birthday gift, Christmas present or personal treat.