T type nut A return-tube is setup on the cut surface of the nut, so that the return-tube does not project from outside of the nut.
N type nut The nut thickness is kept to the thinnest possible so that the return tube projects from the outside diameter of the nut. This nut, of a smaller outside diameter makes it possible to use a screw shaft of bigger diameter in the same space
Z type nut A return-cap recirculation system makes use of the advantages of T-type and N-type nuts. This type of internal recirculation reduces the diametric size to a minimum and avoids unnecessary projections.
E type nut unique recirculation system can be used with an extra lead for high speed applications. This system allows high speed operation without changing of DN value by using a high lead of twice the shaft diameter.
I type nut A prelading condition can be obtained by a single nut as same as a double nut and is adjusted by changing the pitch of each of the circuits in the nut.