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 Internal SSD, 128GB PCIe Gen3 x4 NVMe Solid State Drive, M.2 2230 M Key, Speeds up to 2000 MB/s read and 1000 MB/s write, OEM Package - Newegg.com
New Original Pm991 Klfggar4aa-k0t0 For Nvme Enterprise Server Solid State Drive 2230 1tb - Buy Pm991 Klfggar4aa-k0t0 Product on Alibaba.com
Samsung PM991 M.2 NVMe PCIe 3.0 SSDs
1TB M.2 2230 NVMe PCI Express 3.0 x2 SSD (Solid State Drive)-30mm Half Size, Brand : Samsung PM991 MZ-VLQ1T00, KLFGGAR4AA-K0T0 For Microsoft Surface Pro X, Microsoft Surface Pro 7+, Microsoft Surface Laptop