https://www.techpowerup.com/319266/gigabyte-intros-gen-4-4000e-m-2-nvme-ssd
 
GIGABYTE today introduced the Gen 4 4000E line of value M.2 NVMe SSDs that take advantage of the PCI-Express Gen 4 host interface, as it says on the tin. These drives form the company's new entry level M.2 NVMe SSD series. The drive comes in 250 GB, 500 GB, and 1 TB capacities, and are really targeted at the crowd that likes to pick up well-priced processor+motherboard+DRAM+SSD bundles in the DIY retail channel. The company didn't specify controller and NAND flash type, but we gather from the specs sheet that it uses a DRAMless controller.

The 1 TB variant (model: G440E1TB) offers sequential speeds of up to 4 GB/s reads, with up to 3.9 GB/s sequential writes. The 500 GB and 250 GB variants offer speeds that don't really need Gen 4 bandwidth. The 500 GB model (G440E500G) does up to 3.6 GB/s sequential reads, with up to 3 GB/s sequential writes. The 250 GB (G440E250G) model offers 3.5 GB/s reads, with up to 1.8 GB/s sequential writes. Endurance is rated at 320 TBW for the 1 TB model, 300 TBW for the 500 GB model, and 150 TBW for the 250 GB model. All three models are backed by 3-year warranties. The company didn't reveal pricing.
 
I assume this is for the budget market.