Prior to purchasing this product, go to the official website for a list of products that you can place in these tubes. I use Shu Uemura Hair Oil and a facial scrub that contains jojoba beads within the scrub. I notice over a period of one week the hair oil and facial scrub became nearly solid and unusable. The silicone seems to react to products that have a warming component. Although this is a convenient product for travel, it's just not suitable for all liquid products. I'll stick to Nalgene for now.