So I guess you didn't have them custom made... someone else did?

Nothing passive or aggressive implied, just pertinent info. I'm not interested in buying, but know people who could certainly use panels like these for a good price.
From their site, it looks like 18 or 36oz wet laminated, or 18oz bonded are options.
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Available in welded and non-welded quality PET, PVC or PE Foam(80 kg/m3 density).
Special Features:
- M1 burn resistance certificate (PET)
- Great fatigue resistance
- Good chemical resistance
- CarbonFoam PET is 100% recyclable
Chemical resistance and corrosive gases:
Good resistance against weak bases, weak acids as well as against most current solvents : alcohol – acetone – perchlorethylene. Limited resistance – check in each case – against strong mineral acids. CarbonFoam does not emit any corrosive gases, even when burned, unlike PVC foam. CarbonFoam PET does not emit gases that contain halogen such as hydrochloric acid.
Water and resin absorption:
Excellent closed cell ratio, comparable to PU, SAN and PVC foam.
Certifications:
CarbonFoam has been awarded FST M1 spec burn certificate. Other industry specific certifications are pending and available upon request. Independent laboratory structural testing results available. Check
www.Carbon-core.com for periodic updates.
Specifications:
Variations of CarbonCore lightweight high-performance panels are virtually infinite and may be made to order. The most common options and their corresponding product codes are listed below. Please contact your Carbon-Core Corporation representative for assistance or a question on variations on options not listed.
Standard tolerances are listed below. Please consult with your Carbon-Core representative if a situation requires alternative specifications.
Panel size: 10X50
Thickness: Varies with laminate type and customer specifications, core thickness up to 20″ available by special order. Tolerances =+ .0025″
All Carbon-Core laminated products can be supplied CNC cut to size as per customer specifications.
Carbon-Core limits its warranty to the free delivery of panels replacing panels deemed defective by Carbon-Core Corp. Carbon-Core expressly disclaims any liability for consequential damages.
Several products offered by Carbon-Core Corp are ISO 9002 quality certified.
18PFGLAM
18 oz Pre-fab Adhesive bonded glass Available white pigmented and gel-coated.
18WLGLAM
18 oz wet laminated glass W/R Available white pigmented and Gelcoated
36WLGLAM
36 oz e-glass W/R laminated