That looks a lot like Ryuji Suzuki's recipe:

Neutral Rapid Fixer

Ammonium thiosulfate 120g
(or 60% solution 200 ml)
sodium sulfite 15g
sodium metabisulfite 5g
water to make 1.0 liter
target pH 7.0 plus/minus 0.5

This fixer gives rapid fixing and rapid washing, same benefit as what's claimed for alkaline fixers, but with minimum of swelling.