Prym offers these spiral-shaped pins with a discrete plastic cap for affixing loose covers for sofas and chairs. They are easily screwed into the cushion on the corresponding area through the loose cover, thereby providing reliable support. They can just as easily be screwed out and re-used to clean and wash the cover. Loose cover pins are made of rust-free brass. Their transparent plastic caps have a toothed edge and provide the perfect grip when screwed in.