Cannabis flower that is finely ground and rolled ahead of time is commonly known as a pre roll, joint, or blunt. More adventurous consumers might experiment with infused pre rolls that contain cannabis concentrates to amplify the flowers’ entourage effects, enhancing flavor and potency. Pre rolls typically have an immediate onset with effects lasting an average of  2 - 4 hours.   
                                                                                                                                                                                                                                                                        Description courtesy of Jane