This is the five pockets of Stillpoint technology, large, three pounds each, and three inches in diameter isolation foot. It has received rave reviews.
I have eight of them for sale. The price is $1600 for four and $3100 for eight. They have been used under my speakers. Unfortunately, they don't attach properly with my speakers. They are boxed eight to the box and would be shipped all in the oriigal box that way were you to buy all eight.
M8 to 1/4 20 thread converters (8) are included.
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The weight shown below is for all eight.