Most modern 'fast charging adaptors' will work fine. It MUST support 9v above 1 amp for spectrum 48K. Built in switch, handy for use on ZX Spectrum. USB C input.
ZX Spectrum Clone - (White) ZX Sizif-512 - E1 - With WiFi and Bluetooth Modules
ZX Printer for ZX81 or Sinclair ZX Spectrum ZX Printer EW01
Sinclair ZX Spectrum 48K with composite mod and recent keyboard membrane
Vintage Sinclair ZX Spectrum +2 Home Computer Bundle With Games And Joysticks
Sinclair ZX Spectrum +2 computer with manual and cable
Sinclair ZX Spectrum 128K +2 (Grey) with Original PSU and SCART Lead -Tested