All 4 ESP-01 have been tested with the flicker circuit and all work fine. So far I've made an IOT button with one and it's been working for a week now. You can find them cheaper but nothing beats 2 day shipping! I used a serial USB ESP8266 wifi module for programming along with a soldered button to enter programming mode.
π‘ Izokee ESP-01 Serial WiFi Transceiver Module with USB Converter, Compatible with Arduino
8 Review
π Gigabit Ethernet Media Converter, Single Mode Dual SC Fiber, 1000Base-LX to 10/100/1000Base-Tx, up to 20km, 2-Pack
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π‘ CM19A R.F. PC Transceiver for X10 Devices
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TRENDnet TC-TP1 Network Signal Testing Probe with Adjustable Volume, Speaker and Compatibility for TC-NT2
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π Juiced Systems Silver BizHUB USB-C Multiport Gigabit HDMI Hub with 3 USB 3.0 Ports, Gigabit Ethernet, 4K HDMI, SD/Micro SD, and USB-C Power Delivery
11 Review
π uni USB C Hub with Ethernet Adapter, 4K HDMI, Gigabit Ethernet, and 3 USB 3.0 Ports for MacBook Pro, iPad Pro, XPS
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UGREEN USB 3.0 Ethernet Adapter Hub with RJ45: Fast Gigabit Ethernet Converter, 3 Ports USB 3.0 Hub Compatible for MacBook, iMac, Surface Pro, Chromebook, Laptop, PC
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HB-UMLS Sabrent USB 2.0 Hub with 4 Ports and LED Power Switches for Each Port
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