Baby Shark kid's headphones are adjustable and suitable for children aged 3-7 years. The maximum sound level is set at 85dB which is the level deemed safe for this age group. Please bear in mind they will sound quieter to adults as their hearing is not as sensitive as young children. These wired headphones are compatible with all devices using a universal 3.5mm jack. Please note certain devices will require a 3.5mm headphone jack adapter (not included) and PCs with pink and green jacks will require a splitter cable (not included). TECHNICAL INFO: Driver: 40mm, Impedance: 32 ohms, Frequency response: 20 -20000hz, Sensitivity: 85dB ± 5dB, Connector: 3.5mm stereo jack, Cable length: 90cm