Fragmentation Threshold and RTS Threshold

[libra1310]

Hi
I've noticed that the Asus RT-N66 has the RTS threshold setting under the wireless professional tab (default 2347) but there does not seem to be a setting for the Fragmentation Threshold.
Was reading that if one tweaks the RTS Threshold, we must also tweak the Fragmentation threshold to be lower than the RTS.
So how do we change the Fragmentation threshold if we want to change the RTS threshold?
Anyone can advise??
THanks

[libra1310]

Anyone knows what the default unstated fragmentation threshold is for the RT-N66U?
Can't seem to find the information anywhere...
Thanks

[RocketJSquirrel]

# nvram show | grep frag
wl1_frag=2346
wl0_frag=2346
wl_frag=2346