Seeed-315 Mhz-RF-Transmitter-&-Receiver-Link-Kit-Seeed-Studio-113990017-P-The-315 Mhz-RF-Transmitter-&-Receiver-kit-from-Seeed-Studio-consists-of-one-transmitter-&-one-receiver-&-is-useful-for-remote-control-projects-that-don-t-require-two-way-communication-To-attach-one-of-these-modules-to-a-microcontroller-you-need-to-supply-power-&-1-digital-data-line-so-it-s-very-light-in-terms-of-GPIO-pins-P-P-Seeed-provide-technical-documentation-example-projects-&-software-libraries-on