Sprayon® WL744 and WL745 Welding Defect Detector System is a two-part quality assurance system that detects and locates cracks and defects in metals and non-porous, non-metal parts. Detect and clearly mark even the finest faults in welds, casts and other non-porous materials before they cause product failure or costly breakdowns. Ideal for short run applications or spot-testing large parts, welds, assemblies and more.