Amazon.com: Vilros Pin Header Set for Raspberry Pi Pico : Electronics
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
SMT 2×20 Low Profile GPIO Female Header for Raspberry Pi HAT | UUGear
Raspberry Pi Documentation - Raspberry Pi hardware
Stacking GPIO Header for Raspberry Pi 20×2 Pins | UUGear
PiBorg | 40-Pin (2 x 20) Male Header - Raspberry Pi Zero
Stacking GPIO Header for Raspberry Pi 20×2 Pins | UUGear
40-pin GPIO Header for Raspberry Pi (color-coded) | Elektor
Raspberry Pi Extension Connector (extra high) | Elektor
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
Raspberry Pi 40-pin GPIO Short Pin Expansion Header - Spell Foundry