Specification:

Note: We suggest opening speaker vent hole after receiving speaker port tube!

Due to manual measurement,please allow 0.5-3mm deviation

"16x37x43mm" means "Opening Hole Size is 16x37mm, Height is about 43mm"

Error: ±3mm

​Please see the detail dimension drawing

Loudspeaker box Inverted holes, also called speaker reflex tubes, are commonly used in inverting speakers. They mainly overturn the sound of the loudspeakers in the box, and the sound pressure of the front speakers and the speakers are overlapped to produce a bass effect.

Installation: it is not difficult to install the phase inversion hole, that is, open a hole first, and then gently plug the phase inversion hole. The step is to set the center point of the opening of the box shell, adjust and measure the opening tool, first open a hole on the useless plate, check whether the jacketed sound cylinder is ideal, and then open a hole on the box shell. If the hole is small, you can use the trimming machine to repair it larger. If the hole is large, you can stick it on the sound cylinder with adhesive or with the sealing gasket sold by our store, and then plug it

Package Included:

Port Tube x 1

• All items will be shipped to worldwide.
• All items will only be shipped to the ebay address, so please make sure to provide us with the correct, precise, detailed shipping address at ebay. 
• Customs duty is obligation and liability of a citizen in your country, so the buyer should be responsible for any tax and custom duty incurred.
• Most of the items will be shipped by China Post / Hongkong Post / Singapore Post.
• The shipping time as the follow table is just for your reference. (Note: Brazil/Russia/Ukraine/Mexico/Argentina/Colombia/Chile will take much
  longer time than other countries, so the refund time will be up to 55 days.)

• We only accept payment via PayPal.
• Payment must be completed within 7 days.        
• Please leave messages for your special requests (e.g Color or Size.) in the paypal notes section when you place the order. 

• All the items will be tested before shipping. Buy them with the confidence!
• If the item is defected when you receive it or you are not satisfied with it, you can email us for a replacement or refund, but you have to return the item to us within 7 days.Please contract us and double check the return address before you return it.
• No accepting to return the electronic components.
• Full refund when receiving the original item. Notice: Return shipping fee is paid by the buyer.       
• We maintain the excellent service standards and strive for 100% customer satisfaction! Positive feedback is very important to us,so if you have any problem, please do feel free to contact us before leaving us any Neutral or Negative feedback, so that we can satisfactorily address your concerns.

• We strive to provide you with the best service, and we will reply your question within 24 hours. 
• Our greatest goal is to meet the maximum demands of the customers. 
• Business time: 9:30~21:30 (GMT+8)