I have added some height and 3 little notches so the dampeners wont fall out.
I had those shock absorbers already, so I have chosen this design over the squash ball thing – and they are working very well.
In case you want to buy them, they are called „OEHLBACH Shock Absorber, elastisch schwarz (55038)“. They are not so common outside Germany, I guess, but here are some links.
Amazon Links*:
DE: https://amzn.to/2XyQ03y
UK: https://amzn.to/2Kw4PQn
US: not found
*The used link is a so-called affiliate one. When you buy the product using this link, I will receive a small provision. The price itself does not change because of the affiliation. Thanks for your support 🙂