Zerk fittings

[Jim Myke]

Went thru the forums and couldn't find the answer so here goes, some of my zerk fittings are bad on my gen 2 rt 10, I'm replacing them all, anyone know what size they are?

 

[GTS Dean]

Most likely 1/8" NPT if about the same size as the grease gun attachment itself. If they have a larger hex base, then 1/4" NPT