You can make your own. I use posterboard that I get form Office depot, and just cut it. It weighs nothing and lasts for ever (surprisingly). Easy to replace.
Actually, posteboard is perfect as the foam is a heat insulator.
note: you can add things to this; like extra pieces for the rear for lift, which is what I do so that there's also air flow under the laptops. The edges tend to be a bit ragged but the stuff, for some reason doesn't fall apart, even with constant use (you can also just use masking tape, (or whatever), and tape up the edges.
I've been using this for years. Works really well, and weighs nothing as it's just super light foam. (you can also get this type of posterboard at Walgreens, etc., in school/office supplies (comes also a marker boards).
Actually, posteboard is perfect as the foam is a heat insulator.
note: you can add things to this; like extra pieces for the rear for lift, which is what I do so that there's also air flow under the laptops. The edges tend to be a bit ragged but the stuff, for some reason doesn't fall apart, even with constant use (you can also just use masking tape, (or whatever), and tape up the edges.
I've been using this for years. Works really well, and weighs nothing as it's just super light foam. (you can also get this type of posterboard at Walgreens, etc., in school/office supplies (comes also a marker boards).