The Boss CH4220 speakers each deliver 200 watts at max power providing deep bass and loud crisp sound without any distortion. Each speaker features a red poly injected 1 inch cone with foam surrounding and a 1 inch High-Temperature Aluminum Voice coil. They each have 100 watts RMS power for loud clear audio plus they have a mounting depth just over 1 1/2 inches.- Sensitivity: 90 dB 1 Watt/1 Meter- Poly-Injected Cone with Foam Surround- 1" High-Temperature Aluminum Voice CoilCONE: Made From Polyurethane The CH4220 4 Inch Car Speakers Provide a Resilient And Durable Material That Can Offer Great Sound With The Advantage Of Long Lasting SpeakersVOICE COIL: Our Voice Coils Are Able To Withstand High Temperatures Yet Maintain Its Strength And Fatigue Properties Giving Them The Advantage Of Longer Play Times With Lower WeightsSURROUND: We Use Rubber In A Lot Of Our Speakers. It Has The Ability To Endure Much Punishment Without Any Sign Of Damage. It Compliments The Whole Structure Of The Speaker By Allowing Constant Abuse Where It Is Most Needed Without The Wear And TearTWEETER: A Piezoelectric Tweeter Is More Resistant To Overloads And Can Be Used Without A Crossover Due To Its Electrical Property.