Edge that does not obstruct airflow

I purchased from amazon.de (https://www.amazon.de/dp/B00JFV38P4/ref=pe_27091401_487024491_TE_item?th=1) as a safer alternative to traditional bumpers. Since the child slept little in their crib, it remained unused. The bumper prevents arms and legs from getting stuck between the slats, while not posing a risk of blocking air flow. More detailed description in the pasted Amazon link.