Bass Trap or Snake Oil

Regardless of whether it does anything (doubtful), someone will buy it and swear it parted the clouds and lifted them to audiophile nirvana. 

All of these contraptions that claim to absorb bass waves are useless. However hope springs eternal!

This is a small bass trap that works. I have one.

https://bagend.com/products/series/active-bass-trap-by-bag/

@jperry  Could you verify?  You refer to something different called 'E-trap'.

The E-trap is a tunable electronic bass trap