The debut EP by post-industrial band How to Destroy Angels was first released digitally, for free download, on June 1, 2010; Trent Reznor also released The Slip, Nine Inch Nails‘ seventh album for free download, from his independent label, The Null Corporation.
As with Nine Inch Nails' ‘Halo numbers’, HTDA have ‘Sigil numbers’, for which this record is titled SIGIL 02.