Name: Watford 200/400/800k Disk Drive more
Manufacturer: Watford Electronics
Price: £129.00 (200k), £149.00 (400k), £175.00 (800k)
Blurb: Disk drives... !
Source: Your Spectrum issue 11

Name: Watford Centronics/RS232 Interface more
Manufacturer: Watford Electronics
Price: £29.95
Blurb: Centronics port. Bi-directional RS232 port.
Source: Your Spectrum issue 11

Name: Watford SP-DOS more
Manufacturer: Watford Electronics
Price: £99.00
Blurb: Disk interface with on-board DOS. Supports drives up to 800k.
Source: Your Spectrum issue 11
Read the feature

Name: Wear Saver more
Manufacturer: Computer Add-ons
Price: £9.50
Blurb: Saves wear and tear on your ear/mic and power sockets.
Source: ZX Computing Feb/Mar 84

Name: Wico Trackball more
Manufacturer: CGL
Blurb: Track ball working from any standard joystick port.
Source: Sinclair User Feb 85

Name: WSS Input/Output Port more
Manufacturer: William Stuart Systems Ltd
Price: £25.50

Name: WSX Mk1 more
Manufacturer: Wessex Microcomputers
Price: Under £300 !
Blurb: Interface that allows the Spectrum to be connected to other computers like the C64 and BBC, and allow data to be transfered between them. Uses the IEEE 488 connector.
Source: Sinclair User Feb 85
Note: Due to be launched soon, but was it ever released ?