M25*0.75mm Thread is for Nikon and Leica microscope objective lens thread
size.
M26*0.706mm Thread is for Mitutoyo microscope objective lens thread size.
M27*0.75 is for Zeiss microscope objective lens thread size.
M32*0.75 is for some Nikon microscope objective lens thread size.
Standard RMS Thread is widely for Olympus microcope objective lens thread
size.