{"product_id":"nike-mens-acg-ultrafly-spruce-fog","title":"Nike Men's ACG Ultrafly \"Spruce Fog\"","description":"\u003cp\u003eThe Nike ACG Ultrafly builds on the success of its predecessor with a smoother, more refined ride for trail runners chasing speed over long distances. Designed for racing and high-performance training, it combines Nike's most advanced cushioning with trail-specific grip and a more compliant carbon plate to inspire confidence across technical terrain.\u003c\/p\u003e\n\u003cp\u003eAt the centre of the shoe is Nike's ultra-responsive ZoomX foam, delivering exceptional energy return while maintaining a stable platform for uneven trails. An updated heel construction leaves the foam exposed to increase responsiveness, creating softer landings without compromising control during long days in the mountains.\u003c\/p\u003e\n\u003cp\u003eA full-length carbon-fibre plate sits within the midsole, tuned to be slightly more flexible than the original Ultrafly. This refined construction improves trail feel and adaptability across technical terrain while still delivering the efficient propulsion needed for racing and ultra-distance efforts.\u003c\/p\u003e\n\u003cp\u003eThe lightweight engineered mesh upper is designed to perform in changing conditions, offering excellent breathability while draining water quickly after river crossings and wet sections of trail. Underfoot, a Vibram® Megagrip outsole provides outstanding traction across wet rock, loose gravel and hard-packed trails, giving you the confidence to maintain speed when the terrain becomes more demanding.\u003c\/p\u003e\n\u003cp\u003eWhether you're lining up for an ultra-distance race or tackling big days in the mountains, the Nike ACG Ultrafly is engineered to help you move efficiently from the first climb to the final descent.\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eZoomX Foam: Ultra-responsive ZoomX foam midsole delivers Nike's highest energy return with a stable feel for the trail. The foam is 'unwrapped' in the heel for even better responsiveness.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eBreathable Mesh Upper: Don't worry about puddles or streams—the upper is made for water drainage. It's also lightweight, durable and breathable.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eMore Flexibility: Tackle technical terrain with the full-length carbon-fibre plate. We reduced the stiffness compared to the original Ultrafly for better control on the trails.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\n\u003cspan\u003eEnhanced Grip: Go the distance with Vibram® Megagrip outsole. It's designed to give you durability and enhanced grip on wet terrain.\u003c\/span\u003e\u003cspan\u003e\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli\u003eColourway: Spruce Fog\/Black Spruce-Sea Glass\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eProduct Code: HF5668-300\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eTechnical Specifications:\u003cbr\u003e\u003c\/strong\u003eIntended Use: Trail Running \/ Trail Racing\u003cbr\u003eSupport: Neutral\u003cbr\u003eWidth: Regular\u003cbr\u003eWeight: Approx 290g \u003cbr\u003eDrop: 8.5mm (37mm heel vs 28.5mm toe)\u003cbr\u003eLug Depth: 3mm\u003c\/p\u003e","brand":"Nike","offers":[{"title":"7","offer_id":57053360193860,"sku":"HF5668-300-7","price":219.0,"currency_code":"GBP","in_stock":false},{"title":"7.5","offer_id":57053360226628,"sku":"HF5668-300-75","price":219.0,"currency_code":"GBP","in_stock":false},{"title":"8","offer_id":57053360259396,"sku":"HF5668-300-8","price":219.0,"currency_code":"GBP","in_stock":false},{"title":"8.5","offer_id":57053360292164,"sku":"HF5668-300-85","price":219.0,"currency_code":"GBP","in_stock":true},{"title":"9","offer_id":57053360324932,"sku":"HF5668-300-9","price":219.0,"currency_code":"GBP","in_stock":false},{"title":"9.5","offer_id":57053360357700,"sku":"HF5668-300-95","price":219.0,"currency_code":"GBP","in_stock":true},{"title":"10","offer_id":57053360390468,"sku":"HF5668-300-10","price":219.0,"currency_code":"GBP","in_stock":true},{"title":"10.5","offer_id":57053360423236,"sku":"HF5668-300-105","price":219.0,"currency_code":"GBP","in_stock":true},{"title":"11","offer_id":57053360456004,"sku":"HF5668-300-11","price":219.0,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0868\/5980\/9092\/files\/AURORA_HF5668-300_PHSRH000-2000.jpg?v=1785411529","url":"https:\/\/www.outandbackstore.com\/products\/nike-mens-acg-ultrafly-spruce-fog","provider":"Out \u0026 Back","version":"1.0","type":"link"}