I posted the original description of Timbrens for sale. I also appreciate the listing and suggestions of three products and I have been amused by several posts
First, the three web links show quite a different product. But, thanks for posting them. I looked at the links; but, I have no idea of their effectiveness.
Second, I am puzzled by references to Canada and "rubber springs" by one poster--I simply don't understand the meaning or purpose of the comments--unless they are meant in good fun.
If you look a the Timbren web site, you can learn what they are; and, you likely will see Timbren uses the term "rubber springs." I have not found any American made similar product.
www.timbren.com
Timbrens are, in fact, engineered rubber springs. That, is they are designed for application to specific trucks. They are not a "bladder type." Take a look, now that the subject has drawn some discussion; one can see how they are made and what they look like.
I certainly am not offended by the comments; but, I am puzzled.
In addition, I don't work for the company and I don't own stock. But, they are a good and useful product for certain applications.