Melamine foam is more absorbent and less flexible than the cheaper dark grey Polyurethane soft foam. A bit fragile in hard pressure, so treat it gently. Do not bend. It wil break.
It can be cut easily. Better to have a long blade so that you cut it in one pass.
I needed more than half a cartridge of t.akustik Contact Glue for a large 1x1 piece. So, you would need at least 2 cartridges for all 4 pieces. Better get 3.
The glue performed very well , both on wall and ceiling. I left it 10 mins to rest before placing the panels on the wall or ceiling. Press lightly on all corners and center.
Appilcation of the glue: for small pieces I followed the instructions (Absorber WAS-7 gray - INSTALLATION - t.akustik video on youtube) .
For large piece (1x1) I added extra vertical and horizontal lines of glue in the center - making 4 squares of 50x50cm , plus an X pattern in each square.
The color is light grey. My walls or ceiling are not pure white, this color blended nicely, better than the white version.