After taking the K&F Concept ND8&PL, ND16&PL, ND32&PL, and ND64&PL filter kit along on a full mountain hike with my DJI Osmo Action 6, I came away genuinely impressed.The filters feel solid and well made, which was reassuring when swapping them out in windy conditions. Despite the rugged build, they’re surprisingly lightweight and didn’t interfere with the camera’s white balance at all — something I was slightly concerned about before setting off. Each filter clipped on securely and fit perfectly, with no play or vignetting.The range of filter strengths really proved its value throughout the hike. Lower ND levels were ideal in shaded forest sections, while the stronger ND32 and ND64 came into their own above the treeline in harsh midday sun. The built-in polarisation helped cut glare off rocks and the water in the streams, while deepening the sky and improving contrast. For both stills and video, the results were noticeably smoother and more cinematic, especially when filming walking shots or panoramic views from the ridge.On reflection I'd say this kit felt purpose-built for outdoor adventures. Durable enough to handle a demanding mountain hike, light enough to forget it’s there, and versatile enough to adapt to constantly changing light conditions — a great companion for anyone using the Osmo Action 6 in bright, high-altitude environments.