G43
From CNC.xyz Wiki
The Tool Offset G-Code, also known as G43 is used to retrieve stored tool length offsets that can be utilized during an Automatic Tool Change ATC operation using the M-Command M06. This command allows for changing the tool without having to re-zero the Z-offset.
Standard Format: G43 H00
Here the number after the H represents the desired tool number. H0 is a valid tool number. To clear the command and set a zero value offset, the number 0 can be used in place of the H-command.
Code Examples
In this example, Tool #5 will have its offset selected.
G43 H5
As a follow up example, Tool #2 will have its offset selected.
G43 H2
To clear all offsets and use zero offset, the following command is useful.
G43 0
An alternative to clearing the tool offset is to use the G49 command to clear the offset.