-Our water tank connection is made of high quality brass and the surface is polished. The rain barrel connector is rust-resistant, corrosion-resistant, durable, and suitable for use in various weather conditions. --Water tank seals use safe and environmentally friendly materials, non-toxic and odorless, will not pollute water resources. We provide you with rubber seals to ensure that no water leaks. Specification: length 39mm. Internal thread: 1/2 inch (through hole) External thread: 20mm. Packing: 1x water end screw fitting, 2x sealing rubber. Please confirm the size before purchasing. --You can easily attach an outlet tap to your water tank by the barrel connection. It does not require any tools to install and is easy to uninstall. Our precise sealed hose parts ensure perfect watering. --Universal water tank interface can be installed on various barrels, containers or as a watering device Perfect. Brass water tank seals can be used for water tanks, rain barrels, buckets, water tower faucets and pipes.