Cool for Cats bassline - chorus, phaser or flanger

[JJTee]

Caught this on Pick of the Pops earlier and the bass, and the very heavy use of effects, caught my ear. Found the isolated track and out of curiosity I was wondering if this is a very heavy chorus effect, or flanger? (Or maybe phaser, but thought not). Anyway, it’s very effective (pun intended…):

https://youtu.be/AYtG3NSJ5CU?si=4WG4ym4_o98_laVT

[Dad3353]

Envelope follower..? 

[BigRedX]

Could be an EHX Bass Balls?