Vivobarefoot Primus Trail FG 3.5 are lightweight trail trainers designed to deliver a barefoot-like connection to the ground while providing firm-ground traction for varied terrain. Key attributes: White | White grey | Polyester mesh | Breathable mesh upper | Firm-ground outsole with textured arch for zonal grip | Thin, flexible sole for enhanced ground feel | Lightweight construction | Quick-lace system with toggle | Ortholite performance insole | Replaceable laces and insoles | Low-cut trainer silhouette | Mesh upper with supportive overlays | Multi-directional lug tread | Subtle side branding | Dimensions & fit: Weight: 281 g (single shoe, EU 42) | Fits true to size | Thin sole: 3 mm base; 2.5 mm lug height | Composition & care: Upper vamp: 100% polyester mesh | Overlay: 95% polyester / 5% spandex | Lining mesh: 100% polyester | Lining microfiber: 80% polyester / 20% polyurethane | Laces: 100% polyester | Insole: Ortholite performance foam: 98% polyurethane foam / 2% water-based binding agent | Outsole: 90% synthetic rubber / 10% natural rubber | Brush off mud and clean with a damp cloth. Remove insole and dry at room temperature; keep out of direct sunlight and avoid placing on a radiator. Reapply a textile protector as needed to maintain water-repellent properties.