Originally Posted by
Light Dependant Resistor
Use rubber surrounds, foam rots, hence the silliness of re-foaming because in 12-15 months
you are likely just to have to do it all again. Rubber surrounds, last a lot longer. .....
Jerry at post #3 from the wam site " I was a bit concerned about possible foam rot on the drivers, but when I arrived to pick them up the surrounds looked pristine. Yup, the seller confirmed, newly done - should be good for another 15-20 years! I was mighty pleased with that."
Foam would not last 15-20 years, so likely rubber was used. Perhaps Jerry can confirm