COMPLIANT WITH ALL RELEVANT STANDARDS:With Haisstronica 660PCS ( A.W.G.:22-16 300PCS,16-14 220PCS,12-10 140PCS) heat shrink waterproof wire connectors are compliant with ROHS, ISO 9001:2008, SGS, and CE standards..CONTINUOUS INNOVATION:Solved the collecting problem of connectors caused by the easily damaged box after the work of wiring. The Haisstronica product team tries our best to "Make Work Easier"..HIGH-QUALITY COPPER CORE:Heat shrink butt connectors use a copper core with a higher thickness rating. This makes your connection project safer and better meets our customers’ quality needs!.HIGH-QUALITY HEAT SHRINK:Translucent heat shrink tubing provides high tensile strength and resistance to stretch and minimize mechanical damage. The thick barrel ensures a strong crimp every time. The inner wall of the heat-shrinkable tube has enough hot melt adhesive to ensure waterproof performance reliability. Your wire will never slip out of these heat shrink wire connectors..STORAGE BOXES:The bottom of the storage box HS-T1A, is made of PP material, and the lid is made of high-permeability ABS, which is sturdy and durable. Easy to clean. Easy to assemble.