Cisco QSFP-40G-SR4 Compatible 40GBASE-SR4 QSFP+ 850nm 150M DDM MTP/MPO MMF Optical Transceiver Module

Will choose QSFPTEK next time, their professional service, good enough price and good quality products, that's the reason.

I've been using the 40G optical modules for a few months now in a busy data center, and they've been working like a charm. The speed is steady, and we've seen a big boost in data transfer rates compared to the old equipment. Setting them up was a breeze, and they fit right in with the infrastructure we already had.

QSFPTEK keeps things super organized, so it's easy to track down what I need. The sales team is friendly, knowledgeable, and quick to respond to any questions or requests.

Since our company has a lot of video business, there is a great demand for bandwidth. This 40G Ethernet upgrade task was completed with this 40G QSFP+ module, which greatly improved our bandwidth and reduced the task burden in the video work system.

The product quality is excellent—definitely a 5-star rating! Plus, the price is super low, which makes it really appealing to us!

This is my third purchase here. I noticed their product prices have dropped. It just so happened that I needed some transceivers to upgrade my campus network. This time, I bought 10× 10GBASE-T SFP+ and 4× 40G SR4, and they worked as expected.

Built breakout connectivity using this 40G QSFP+ SR4 module and 10G SFP+ SR. The products used are all from QSFPTEK, you can find all the optical products you need at QSFPTEK!

This 40G SR4 module has good performance, stable transmission, and is very compatible with my equipment. It is also very cost-effective and has a cheaper price than other websites.

Works perfectly on my Cisco ASR 9000 series switches! Not only does QT have a high quality product, their pricing is very competitive and they are definitely a great partner to work with.

I received the package today, and it arrived in about four days, which was faster than I expected. The module looks good, but there are a few differences between the actual product and what was shown on the website. The account manager explained that the pull ring shape can vary depending on the production batch. The one I received matches the picture they sent me before shipping, so that's fine with me. Overall, the customer service, pricing, and shipping speed have been excellent—now it's time to test the quality.