Historical clue formulations

• Beam bent at 90° — 2016-12-01
• 90-degree angle iron — 2015-09-01
• Letter-shaped beam — 2015-04-13
• Bent beam — 2014-03-16
• Letter-shaped shelf support — 2013-12-31
• Angle iron — 2011-11-10
• *Beam with a bend — 2011-01-23
• Angle iron — 2007-10-12
• Beam with a 90 degree bend — 2006-12-19
• Iron brace — 2005-11-27