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Hold stock from the outside, leaving clearance for inside welds, or hold stock from the inside for outside welds.

Hold and position sheet metal, round pipes, square, angled or flat stock.
Inside / Outside angles constructed of two independent magnets for consistent magnetic force
Use mounting holes to link two magnets together for use as fixturing elements.
Use hex hole on magnet for breakaway leverage.
Angles: 90 (30°, 60°)