ZK-TB21 TPA3116D2 Bluetooth 5.0 Subwoofer Amplifier Board (Banggood, Aliexpress: Channel: 2.1, Bluetooth Version: 5.0(no shielding, 4-8Ω, Color: Black, 10m), Material: electronic components, Input sensitivity: 500mV, Audio Input: AUX+Bluetooth, Power: DC12-24V/5A, Model: ZK-TB21, Chip: TPA3116D2(with AM anti-interference function), Adapter speaker: 20-100W (the best price with coupon)).
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Aliexpress
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Banggood
Banggood warehouse is located in China. As you can see I didn’t find any active coupon for this product right now…
Link: Banggood product page
Price: $-3
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Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/feV
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Price history and price alert
Here is price history (for all/most countries) for ZK-TB21 TPA3116D2 Bluetooth 5.0 Subwoofer Amplifier Board. The lowest price was: $15.99.
Price records source(s): Banggood
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You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).