What are the differences between USB WiFi adapters 1T2R and 2T2R, Exp: 6147 vs. 5334?

2T2R stands for 2 Transmitter, 2 receivers. 1T2R stands for 1 transmitter, 2 receivers. So with the 2T2R, you will have a fast upload and down load speed, because you have 2 transmitters and receivers working, you'll also notice those correspond with the 150mbps and 300mbps designations.