Is it that the same as this stuff, just in 4x quart bottles?
Evapo-Rust The Original Super Safe Rust Remover, Water-Based, Non-Toxic, Biodegradable, 1 Gallon,Gray,ER012 https://smile.amazon.com/dp/B00M0TLQ66/ref=cm_sw_r_apan_glt_fabc_2Y8WZVGF3BQGZKCSQKVR