The receptionist trolley passes by: Listen & Download The receptionist trolley passes by .mp3 Error! Change your browser, please! ⇓ Download Knocking, The noise of the elevator ⚠ Sine wave (975Hz) ⚠ Chemistry, Bunsen Burner ⚠ Closing a cigarette case, Opening ⚠ Throw nutshells on the floor ⚠ Room noise ⚠ Football bugle ⚠ Lightsaber battle ⚠ Bone fracture ⚠ The fall ⚠ Movement, Elevator with hand doors ⚠ Bicycle rear wheel ratchet ⚠ ★★★★★