This is we believe what's known as a "drift sight" that once belonged to a British Lancaster Heavy Bomber.  This item came from Australia some years ago. It's designed to allow the bombadier to account for wind-drift before dropping a payload over target.  Overall, it's in fair condition with a couple of pieces missing which include the rubber piece that fits around the lens and one of the dials.  The missing dial was probably gov't-removed before being sold off as surplus decades ago.  A rare and historic World War 2 British aviation item.

Item# 0804

$250