Historical Rules · 5 October 2018
Rule 702.6c
Official source text from the 5 October 2018 Rules release
“Equip [quality] creature” is a variant of the equip ability. “Equip [quality] [cost]” means “[Cost]: Attach this permanent to target [quality] creature you control. Activate this ability only any time you could cast a sorcery.” This ability doesn’t restrict what the Equipment may be attached to.