Estone Welding Gauge Weld Bead Height Welding Seam Gap Boilers Bridges Pipes Ruler Gage (Gap Boilers Ruler) Be used for the measurement of the bevel angle, height, width, gap and undercut depth of weldment Suitable for the detection of boilters, bridges, ships, pressure vessels and oil pipes. It is made of stainless steel It is characterized by portable and compact structure, easy operation and wide application main scale, height gauge, undercut depth gauge, multiple-purpose gauge.