Mega Block™ - Hydrophobic Foam Heat Shield

FREE Standard Shipping Details


FREE Standard Shipping

Free shipping is valid on any order shipped to a single address in the mainland USA. Standard shipping is covered. Overnight or 2-day delivery will cost extra.

Our products are bulky and heavy. Free shipping is hard and expensive.

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How Much Mega Block Do I Need?

Vehicle Class

Call us to discuss your project. 1-800-679-8511

Vehicle Coverage

Estimated Square Footage

0Sq Ft
How do I get exact square footage?
  1. Get a tape measurer
  2. Measure the length and width of each surface
  3. Length x Width = Square Footage

Mega Block - Hydrophobic Foam + Heat Shield


Keep your cabin cool with Mega Block, specifically designed to be a best-in-class heat shield by combining an aluminum reflective barrier with the excellent automotive heat insulation attributes of melamine foam. Mega Block is hydrophobic, lightweight, and flexible while reflecting 98% of radiant heat energy. Use it on the engine side of the firewall, as hood insulation, or any vehicle needing heat control including engine compartment insulation for your boat.


  • 0.5 inch thick hydrophobic melamine foam with an aluminum foil-faced composite bonded on top
  • Lightweight, flexible, water resistant, and Class A fire rated
  • Reflects 98% of radiant energy
  • Each sheet is 24” x 24” (4 Sq Ft) and weighs about 1/2 of a pound
  • Thermal range: -40 F to 1000 F
  • Resists organic solvents, odor free, and meets smoke, fire, and toxicity standards
  • Aerospace grade foam and heat shield (R-value per inch: 4.16)
  • Made in Germany with hydrophobic process completed in the USA


Product Usage

  • Always face foil side of the product towards the heat source
  • Easy to apply with our peel & stick adhesive backing. You need to apply enough pressure for your fingers to "feel" the adhesive bonding to the metal surface.
  • Install at least 2” from the heat source. We recommend foil insulation tape on the edges to protect the foam.
  • Used in non-automotive locations as well, like generator boxes or a soundproof server rack


  • Hood - cover entire lid with foil facing the engine
  • Firewall - engine side
  • For rear-engine design layouts, apply to the vehicle's back wall.


Flammability Ratings:  Description:    Rating:
 UL 94 HF-1  Horizontal Burning  Pass
 UL 94 V-0  Vertical Burning  Pass
 FAR 25.853 (a, i)  60 Sec Vertical

 Burn Time (Avg): 0 Seconds

 Burn Length (Avg): 2”

 Drip Extinguish Time: No Drip 

 FAR 25.856, BSS7365, AITM 2.0053   Radiant Panel 

 After Flame: 0 Seconds

 Flame Propagation: < 1”

 ASTM 662-83, BSS7238  Smoke Generation

 Flaming: Ds (1.5 min) = 57 

 Ds (4.0 min) = 77 

 BSS7239                                      Toxicity                                      Pass
 ASTM E 84  Steiner Tunnel, 1inch thick

 Flame Spread < 25

 Smoke Developed < 50

 ASTM E 162-83  Surface Flammability

 Flame Spread factor 1.83

 Heat Evolution factor 2.50

 Flame Spread index 4.62

 DIN 5510  

 Flammability: S4

 Smoke: SR2

 Drips: ST2


Foil Heat Shield Specifications

 Base Fabric Type:  Plain Weave Fiberglass 
 Aluminum Foil thickness:   0.001 inches 
 Composite Characteristics:  
 Thickness (ASTM-D1777-96):   0.02” (Nominal) 
 Weight (ASTM-D-3776-96):   0.1225 lb/sft (Typical) 
 Tensile Strength:(ASTM-D-5035-95):   Warp-75 lb/in 
   Fill- 50 lb/in 
 Flame Resistance (FED 191/5903-2):   
 Flame Out   1 sec max
 Afterglow  1 sec max
 Char Length   1 inch max 
 Temperature Range:  
 Composite  *-40°F to 1,000°F

 1000°F requires 2” between the

 heat shield and the heat source

 *PSA Temperature Range

 -40°F to 450°F


Acoustical Properties

ASTM E1050 testing method used to record acoustical absorption coefficients at various thicknesses and frequencies.

                                          Frequency (Hz)

Foam Thickness:  125   250   500   1000   2000   4000 
0.25 in. 4 5 10 20 39 81
0.50 in. 11 12 25 42 77 94
1.0 in. 18 23 50 82 99 99
2.0 in. 31 60 75 90 100 100
3.0 in. 42 67 81 96 100 100
4.0 in. 53 80 90 99 100 100

Shipping Cost:
Calculated at Checkout
Project Category:
Material Type:
Heat Shield