Your search for "A4 Styro" revealed the following:

Styrofoam A4, 6mm thick (297x210x6mm): Moline material SB-62

Styrofoam for models, normal size A4, thickness 3cm (210x297x30mm): Molin material SF-35

Styrofoam for models, fine grain, A4 size, 3cm thick (210x297x30mm): Molin material SF-55

Styrofoam for models, normal size A4, 5cm thick (210x297x50mm): Molin material SF-75

Styrene board B4-5P 5mm thickness, 3 sheets : Kougen-do Material Non-scale SB-B4-5P

Styrene board B4-1P 1mm thickness, 4 sheets : Kougen-do Material Non-scale SB-B4-1P

MiraForm ĩ grey A4, thickness 1 cm (210x297x10 mm): Molin material MFG-12

Styrene Paper B4-2P 2mm Thickness 4-Pack : Kougen-Do Materials Non-scale SP-B4-2P

Styrene Paper B4-1P 1mm Thickness 4-Pack : Kougen-do Material Non-scale SP-B4-1P

Styrene Paper B4-3P 3mm Thickness, 3-Pack : Kougen-do Material, Non-scale SP-B4-3P

Styrene board B4-3P 3mm thickness, 3 sheets : Kougen-do Material Non-scale SB-B4-3P

Styrene board B4-7P 7mm thickness, 2 sheets : Kougen-do Material Non-scale SB-B4-7P

Styrofoam for models, fine grain, small, 3cm thick (300x360x30mm): Morin material SF-01

Styrofoam B5 6mm thick (252x179x6mm): Moline material SB-61

Styrofoam for models, normal size, 3cm thick (300x360x30mm): Molin material SF-03

Styrofoam for models, normal size, 5cm thick (300x360x50mm): Molin material SF-12

Black matt (opaque, frosted): EB-314 15314

Stylo board B5, thickness 5mm (252x179x5mm): Moline material SB-51

A4 Wooden diorama base board : Sakatsu Material Non-scale 8841

Curved embankment parts - basic part (2 pieces): Molin material TM-11