GPIO Header for Raspberry Pi A+/B+/Pi 2/Pi 3/Pi 4/Zero [2x20 Female Header] : ID 2222 : $1.50 : Adafruit Industries, Unique & fun DIY electronics and kits
Raspberry Pi 2 Pin Connectors | 2x20 Male Header Raspberry - 4pcs 2 X 20 Pins Female - Aliexpress
Amazon.com: 2 x 20 (40 Pin) Extra Tall Female 0.1 Inch Pitch Stacking Header Compatible with Raspberry Pi A+/B+/Pi 2/Pi 3 Extra Tall Header (Pack of 8) : Electronics
2 X 20 Pin Hammer-in Solderless Pin Headers For Raspberry Pi Pico – Vilros.com
Raspberry Pi 40-pin GPIO 1 to 2 Expansion Board - Micro Connectors, Inc.
40 Pin 2x20 2.54mm pitch Male Header GPIO Raspberry Pi | eBay
Raspberry Pi 40-pin GPIO 1 to 2 Extender – Geekworm
Amazon.com: SB Components 2x20 Pins Extra Tall Female 0.1" Pitch Stacking Header for Raspberry Pi A+, Pi Model B+, Pi 2, Pi 3 and Pi 3 B+ (Pack of 5) : Electronics
GPIO Header for Raspberry Pi 3 and Pi Zero - 2x20 Female, pitch 2.54mm - Melopero Electronics
Raspberry Pi Pico Headers Kit - RobotShop
Female Header Set for Raspberry Pi Pico - PiShop.us