A - Frame : A structure made of two independent columns fastened together at the top and separated by a reasonable width at the bottom to stabilize the unit from tipping sideways
US Department of Labor, Logging eTool: Glossary, Occupational Safety & Health Administration OSHA, Washington, D.C., USA 2010. https://www.osha.gov/SLTC/etools/logging/glossary. html, (OSHA/ Logging - Amer) {620}