I’d like you to know that for all new batches of Skin Treats moiturizing oils, I will be using more costly dropper bulbs made of natural instead of synthetic rubber. I was told that they are much better at resisting chemical reactions when exposed to essential oils compared to synthetic rubber, even at 100% concentration.
And in case your wondering–no, I’m not about to raise prices on account of my packaging cost going up. 
On a side note, I’m a bit amused that while Malaysia is a rubber producer, these bulbs were made in Taiwan. Maybe I’m not looking in the right places, but I would have liked to have found a local manufacturer and supplier of these types of high quality bottles and droppers.