Do not cut a PM991 only the PM991a can be cut to exactly 30mm. The 991 is about 40mm when cut : r/SteamDeck
Samsung PM991 2230 1TB NVME SSD Upgrade BC511 256GB 512GB For Surface Pro 8 9 X | eBay
I tried the Samsung PM991 hack and it didn't work. Validate drive before I cut. Cut past the chips like other posters. Now drive only shows up as 1.1gb and won't format.