The only tools required to assemble models were a screwdriver and spanners (wrenches). The clamps are either mechanical (manually operated using spanners) or air operated varieties. In some parts of Europe, adjustable spanners are often called a Bahco. Some adjustable spanners automatically adjust to the size of the nut. Spanners may be used in computational geometry for solving some proximity problems. The solution can be approximated using geometric spanners. In Australia, adjustable spanners are also referred to as "shifters". The "Theta graph" or "formula 5-graph" belongs to the family of cone-based spanners. It forms a homopentameric channel with ten transmembrane spanners. It is imprinted on the spanners in millimeter (mm) values. The albums "Temple of Transparent Balls" (GPR) and "Spanners" (Warp) followed. Initially, Mariarti's weapon is an infinite supply of spanners. Research has also found that opinion leaders tend to be boundary spanners. Boundary spanners purpose is to filter and transfer information across organizational boundaries. Research has also found that boundary spanners tend to be opinion leaders.