Poor quality. Screw threads are all stripped, due to either the material too soft or excessive force being applied. One of the rubber sealing is also broken. Was the product returned and resold?

Overall, this text is well put together. It has good explanations and examples in each chapter. If you choose to take the time and do the self test questions at the end of each section, the answers are in the back. Also, the end of the chapter problems have answers that you can check your work. I haven't used the supporting web material yet, but there are tools and supporting material to download.

very nice texture compared to the other infant head support pillow that we got. This is somewhat i can compare as a firm foam inside, i mean i do not know what it has inside, maybe the description says it, but it feel like a firm pillow. When you press on it goes down and comes back up. Its not like a memory foam though, i wish it was. This packaged arrived right on time and it was quick, i appreciate the packaging this company did to ensure my product will be protected during the delivery of this product to my house.