A drive bay is a standard area for adding hardware to a computer. Most drive bays are fixed to the inside of a case, but some can be removed.
Origin Storage DELL KG1CH drive bay panel 8.89 cm (3.5in) Bezel panel

Origin Storage DELL KG1CH drive bay panel 8.89 cm (3.5in) Bezel panel

Origin Storage
£19.99
Origin Storage DELL D981C drive bay panel 8.89 cm (3.5in) Bezel panel

Origin Storage DELL D981C drive bay panel 8.89 cm (3.5in) Bezel panel

Origin Storage
£23.99
DELL Caddy for PowerEdge R/M/T 610/710 SATA/SAS 2.5in

DELL Caddy for PowerEdge R/M/T 610/710 SATA/SAS 2.5in

Origin Storage
£29.99
DELL ASSY CARR HD/SSD 2.5 14G

DELL ASSY CARR HD/SSD 2.5 14G

DELL
£18.99
DELL HD Carrier 2.5 Inch

DELL HD Carrier 2.5 Inch

DELL
£26.99
DELL KG1CH drive bay panel 8.89 cm (3.5in) Bezel panel

DELL KG1CH drive bay panel 8.89 cm (3.5in) Bezel panel

DELL
£18.99
DELL D981C drive bay panel 8.89 cm (3.5in) Bezel panel

DELL D981C drive bay panel 8.89 cm (3.5in) Bezel panel

DELL
£21.99
ASUS LSI BBU PCIE BRACKET

ASUS LSI BBU PCIE BRACKET

ASUS
£29.99
i-tec Advance USB 3.0 Slim HUB 3 Port + Gigabit Ethernet Adapter

i-tec Advance USB 3.0 Slim HUB 3 Port + Gigabit Ethernet Adapter

i-tec
£18.99
i-tec Metal USB-C HUB 3 Port + Gigabit Ethernet Adapter

i-tec Metal USB-C HUB 3 Port + Gigabit Ethernet Adapter

i-tec
£20.99
i-tec Advance USB-C Slim Passive HUB 3 Port + Gigabit Ethernet Adapter

i-tec Advance USB-C Slim Passive HUB 3 Port + Gigabit Ethernet Adapter

i-tec
£20.99
HPE ML350e Gen8 v2 8 SFF Hot Plug HDD Cage Kit 2.5

HPE ML350e Gen8 v2 8 SFF Hot Plug HDD Cage Kit 2.5" Bezel panel

Hewlett Packard Enterprise
£120.99