There are two buttons on the plug adapter, You have to slide the "lock/unlock" button to the "unlock" side in order to allow the arms that go into the wall to pop out. Once they are all the way out, slide the button back into the "lock" position.
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Universal Travel Adapter with Dual USB Port UK to EU Plug Adaptor Wall Charger AC Power Converter World for USA EU UK AUS
Aliexpress UK
6 in 1 Universal Adapter for Travel: International travel adapter has 2 AC Outlets, 4 USB (2 USB C), charging 6 devices simultaneously; You can plug devices from diverse countries (except South Africa) into the front universal AC outlet; 2 prong AC outlet on the side, suitable for Japan, USA.
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EU DE Germany socket 3 pin Swiss plugs adaptor Embedded Swiss adapter converter plug Swiss plugs turn to French plugs
Aliexpress UK
Type G(such as UK, Ireland, Singapore) 3. Type I(such as China, Australia, New Zealand). It can cover 224+ countrires plug standards. [Compact Design] You could slide out the pins for use and press the button on the side to recall the pins.
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EU UK US AU GER Standards Plug Travel Adapter Electrical Power Socket Converter Multifunction International Universal Jack
Aliexpress UK
Not suitable for blower. USAMS universal conversion plug socket. Portable universal travel socket rated current.
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EU UK US AU GER Standards Plug Travel Adapter Electrical Power Socket Converter Multifunction International Universal Jack
Aliexpress UK
Decqle Universal Travel Adapter, International Travel Plug Adapter with 2 USB-C(PD 20W) ＆ 1 USB-A Ports, All in One Portable Adaptor, for USA, UK, EU, AU ＆ 224+ Countries (Black). Type G(such as UK, Ireland, Singapore) 3.
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TESSAN Universal Travel Adapter with 2 USB Ports & 3 Type C, International Plug All-in-one Wall Charger for US EU UK AUS Travel
Aliexpress UK
Suitable for use in European and Mediterranean countries, these handy travel plugs convert a UK 3 pin plug into a standard 2 pin mains plug. This plug is an essential holiday item. • Single socket. • 13 amp. • Travel adaptor. • Allows your UK plug to be used in Europe. • For indoor use. • Child resistant sockets.
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World Wide Universal Travel Adapter US/EU/UK/AU Multi Plug Charger With Dual USB 2 Ports Travel Conversion Socket Plug Converter
Aliexpress UK
【All in One Travel Plug Adapter】AUNNO travel adapter worldwide all in 1 design makes it easy to use. Built in UK, EU, AU, US plug, you can easily use it in over 150 countries while you are travelling.
eBay
TESSAN International Plug Travel Adapter Universal with 3 USB Port and 1 Type C, All-in-one Wall Charger for US EU UK AUS Travel
Aliexpress UK
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eBay
TESSAN Universal Travel Adapter Worldwide with USB & Type C, International Plug All-in-one Wall Charger for US EU UK AUS Travel
Aliexpress UK