Equal-i-zer is a brand name, not a type. it has trunnion bars and no chains.
it has 4 point integrated sway control.
it's so popular, its name has become a term for a WDH, like Kleenex for tissue paper.
the other WDH needs an add-on friction sway bar or two of them.
i own an Equal-i-zer so i'm a bit prejudiced. i'm not a fan of the old technology WDHs like the first one. plus you'll need to drill into the A-frame with the cheap one. the Equal-i-zer doesn't require any drilling.
Dan- Firefighter, Retired:C, Shawn- Musician/Entrepreneur:W, Zoe- Faithful Golden Retriever(RIP:(), 2014 Ford F150 3.5 EcoboostMax Tow pkg, 2016 PrimeTime TracerAIR 255 w/4pt Equalizer and 5 Mtn. bikes and 2 Road bikes