WMYCONGCONG 4 PCS 1.5" 4ohm 3W Audio Speaker Stereo Woofer Loudspeaker for Arduino

OK for lower loads, but if you try and drive it at higher volumes it can distort. I used it to replace a blown speaker in a Uniden fixed marine VHF radio. It was the perfect size, but does struggle at higher volumes. All in all its of a quality that would be expected at this price point.

ビビリ音だらけのラジオのスピーカーユニットをコレに取り替えました。こんなに小さいユニットから出ているとは信じられないほどの、バランスの取れた良好な音質に感動。まだ三つも残っているので（笑）何か作ってみようかと思案中です。

Love these little mighty speakers, they are loud and proud. Just a little disappointed that some of the speaker cones were scratched and looked a bit scruffy due to less than ideal placement in the clear plastic box they came in.

MP3デコーダーと合わせて（推奨4Ω3W）、百均のペーパーBOXに組み込んでMP3プレーヤーに。 ペーパーBOXは、厚みのある底板の方に穴を開けて、エポキシ系の接着剤でしっかり固定。 基板上のマイクロUSBポートを使用すると、携帯電話のデータラインからも充電する3.7Vリチウム電池またはUSB 5V、乾電池BOX（単三3本）の使用も可能。百均のペーパーBOXのデザインもいろいろ選べて良いかもです。 電源を除いて、基板、スピーカー、ペーパーBOXで約800円ぐらいで。

I'm using these in a diy drum machine/glorified metronome. I wanted to have some way to hear it without needing to plug into another set of speakers all the time. The size is great for my project. Small speaker, so obviously very little low end. Doesn't sound bad though. I just wish there were mounting tabs/holes.