Trend WRT router table

[MikeJhn]

That label was probably referring to the maximum size bit that can be used with that insert, but if you mount the router bit below the insert and then put the insert in place securely fixed, start the motor and raise the bit up through the insert it will form its own a zero insert for that bit.

 

[UKHopeful]

Because the 625 is the same as the T10 / T11 then you can fit the T11 height adjuster to the 625 although it can be slow to use.

I believe that the T11 base is slightly different to that of the DW625 and the T11's threaded rod is 'double-ended', allowing it to be turned from either above or below the table. You can't just fit that rod to the DW625's base.
I don't know if the T11's base could be fitted to the DW625, but it's expensive anyway, about £90! Another benefit of the T11 base is the optional quick release components.