Resale shop find. What the fuck are these?

Wafers?

File: 20170421_202828.jpg (2MB, 4032x2268px) Image search: [Google]

2MB, 4032x2268px

Says "poly dummies 86"

>>60009357
how can you even somewhat follow tech in 2017 and not know what the fuck a wafer is
unless you're crossboarding which is acceptable I guess

Silicon wafers of some kind but the details aren't easy to see.

>>60009357
http://eandmint.co.jp/eng/wafer/product_detail/product_dummy.html

Dummy wafers (also called as test wafers) are wafers mainly used for experiment and test and being different from general wafers for product.
Accordingly, reclaimed wafers are mostly applied as dummy wafers (test wafers).

Dummy wafers are often used in a production device to improve safety in the beginning of production process and are used for delivery check and evaluation of process form.
As dummy wafers are often used for experiment and test, size and thickness thereof are important factors in most occasions.

In each process, film thickness, pressure resistance, reflection index and presence of pinball are measured using dummy wafers (test wafers). Also, dummy wafers (test wafers) are used for measurement of pattern size, check of defect and so on in lithography.

>>60009393
Poly Dummies Valentines 86 >>60009402
>>60009402
Just asking. Not a lurker of technology. Jesus christ.

>>60009357
Actually you're not even warm. These are high-end hole covers for fingerboxes. I have that violet one that I bought in Italy. These are a good find, OP. Are they metric?