1500RPM version is very quiet (21dBA) and steady spinning, silent airflow that you may not notice.
Dimension of fan: 120mm(L) x 120mm(W) x 25mm(H) / 4.72in(L) x 4.72in(W) x 1in(H); Totally 120x120x54mm / 4.72in x 4.72in x 2.13in.
Rated Voltage: DC 5V; Rated Current: 0.2Amp; Rated Speed:1500RPM; Air flow: 56CFM; Noise: 23dBA
Bearing Type: Sleeve Bearing; Life: working up to 35000h at 25 degrees.
Package include: 1 piece router cooler fan