Sturdy black grommets sized 8 mm (5/16″) for ventilation, lacing and reinforcement on accessories and apparel. The set includes a matching hand tool to install clean, professional‑looking rings that won’t fray fabric edges. Ideal for tote bags, banners, aprons, costumes and home décor. Works best on interfaced woven fabrics, canvas or vinyl; mark positions, punch or pre‑pierce holes, then set on a hard surface using firm, even taps.