Model Variants (Including Prototypes)
MH-53 - Base Series Designation
YHH-53H "Pave Low I" - Prototype Designation
HH-53H "Pave Low II" - Night Infiltrator variant
MH-53H - Redesignation of HH-53H production mark
MH-53J "Pave Low III" - Special Forces variant based on HH-53B, HH-53C and HH-53H production models.
MH-53M "Pave Low IV" - Improved and modernized MH-53J production mark.