What are the differences between Nikwax spray-on and wash-in products, and which one is more effective for waterproofing outdoor gear?

Nikwax spray-on products are applied directly to the surface of outdoor gear, while wash-in products are added to the washing machine during a wash cycle. Spray-on products are more targeted and can be used for spot treatments, while wash-in products provide overall coverage. The effectiveness of each product depends on the specific gear and its care instructions. It is recommended to follow the manufacturer's guidelines for the best results.