I Shape Paver Blocks with Alternating Colours
These I shape concrete blocks interlock each other and in alternating colours of red and grey.

It is a wonderful outdoor texture for backyards and public areas.
 
I Shape Interlocking Paver Blocks
This concrete block has I-shaped structure interlocking each other when they are in offset layout.

It is a fantastic pavement texture for parks and pedestrian pathways.