one similarity between particles and antiparticles

the only similarities between particles and antiparticle is their masses, both particle and antiparticles have same mass, and all other properties are reversed.

 for example, electron and positron have same mass of approximately 9.11 x 10^-31kg  but opposite charge, electron is negatively charge while positron is positively charge , though this opposite charges have same magnitude.

 all other properties for antiparticles of  particles are opposite, this did not stop at elementary particles.

Composite particles also have antiparticles where their  constituent component are opposite to that of original particle, for example baryons have quarks while antibaryons have antiquarks, protons have antiprotons as it antparitcles, other examples are neutrino and antineutrinos, quarks and anti-quarks, neutron and antineutron, all this have same mass but reversed charge.

 how do you identify an antineutron since neutron is electrically neutral?  neutrons have one up-quark and two down-quark while an antineutron has one anti-up-quark and two anti-down-quarks but both have same mass.

 therefore the major similarity between quarks and anti-quarks are their same masses.