Hi, You are buying awesome genuine Genuine Panasonic / Sanyo NCR20700B 4250mAh 15A battery cells imported directly from a Panasonic / Sanyo factory in Japan (yes, they are co-brands and are identical products), they are among the best 20700-sized cells you can buy!

I personally adore the level of quality these are made at, these are bigger than standard 18650s and it allowed them to have much, much finer made components such as positive terminal... they just feel way different, we are currently moving our battery pack production onto these cells!

Excellent reliable cells we are using these to build custom energy-dense battery packs along with Efest IMR 26650 5000mAh but Sanyo are much higher quality and more consistent cells! 

https://www.ebay.co.uk/itm/182953772068.

Official specifications:

Panasonic / Sanyo NCR20700B datasheet

Max Continuous Discharge Current: 15A
Typical Capacity: 4250mAh
Rated Capacity:  4000mAh
Style:  Flat top
Max Dimensions: 70.3mm (L) x 20.35mm (D) 
Max Weight: 63g
Nominal Voltage: 3.6V
Full Charge Voltage: 4.2V
Protected/Unprotected:  Unprotected
Origin:  Japan

I am running a business in industrial design and automation and we buy tens of thousands of these - all are genuine imports, all cells are tested to be same internal resistance for the building of large battery packs, I've decided to give light to retailing of these here.

Shall you have any question or queries, please do not hesitate to let me know.

Thank you.