These high-density concrete blocks from NELCO are designed to provide the optimum amount of shielding in a smaller space than traditional concrete.

The blocks are available in five standard densities: 145, 240, 250, 288 and 300 pounds per cubic foot. If you require a modular shield the blocks may be dry stacked allowing for easy relocation in the future.

NELCO’s UltraShield modular blocks are available in two designs: Our interlocking blocks incorporate an “N” design on 4 sides to ensure the shielding integrity of the seams between blocks. Plus NELCO also supplies square-edge, high-density concrete block.

All NELCO high-density concrete blocks are manufactured under our ISO 9001 accredited quality control program, ensuring that the blocks used in your project will be of the highest quality you’ll find.

Top-Line Tech Specs


6” high x 6” wide x 12” long
Concrete Densities:
145 lbs. per cubic foot
240 lbs. per cubic foot
250 lbs. per cubic foot
288 lbs. per cubic foot
300 lbs. per cubic foot

Custom densities available


Industrial X-Ray
Non-Destructive Testing
Nuclear Power Plants
Radioactive Material Shielding
Cargo Scanning