Allen Aluminium Thimbles, also known as low-friction rings, are a reliable option for high static-load needs and a great alternative to traditional blocks. Made with premium marine grade aluminium and featuring an anodized finish for superior corrosion resistance, these thimbles are ideal for harsh marine environments. In addition, our thimbles are coated with Teflon to decrease friction. With 6 color options to choose from, including black, blue, silver, purple, gold, and orange, these thimbles are also perfect for arboriculture, theater scenery movement, kite surfing, and paragliding.