to determine the part number, follow these easy steps:

first look to the insert, and see if somewhere in the middle or on the top it has a squeezed section, then you know it's a locking insert. the inside threads of the Clinsert is deformed which gives the locking feature

the easiest way to know the insert part number is by measuring it with a caliper tool.

1) measure the outside diameter

2) measure the internal diameter

3) measure the length

4) count the amount of clins

always measure the outside diameter which is the major diameter.

then use below table:

use this specification table for imperial:

use this specification table for metric thread