Questions about the M1 Abrams MBT T158 tracks

I would like to know what is the difference between the 2 types of tracks, T158 and T158LL for the M1 Abrams tank?

T158 tracks have solid center guide teeth.

T158LL tracks have hollowed out center guide teeth and are lighter because of it. T158LL are newer and were introduced on M1A2 SEP tanks. They were also backdated on older tanks.


thanks for the information.