The ultra-containment berm, modular model (aka "Gorilla berm"), has the ability to do something that none of our other berms can do- change its dimensions by using 6-foot long polymer coated, foam blocks for its wall structure, the gorilla berm can very quickly and easily be resized to other shapes and sizes to meet other requirements. The foam blocks also allow the modular model containment berm to be driven in and out of without any manual operation of the walls. The heavy-duty foam compresses to allow trucks and other vehicles to drive into the unit and quickly returns to its normal state when the weight is removed. The triangular shaped, polymer-coated foam support blocks are used with rebar (not included) to provide sidewall structure. Molded in slots in the top of foam blocks hold rebar- secures material in place. Meets spcc and epa container storage regulation 40 cfr 264.175 spill containment regulations. Made in the usa.