Yeah, they are only 6000mah, though. Either they are high drain/low capacity or else below standard. If it had the same chemical mix as the Shockli 5500mah, the mah should be closer to 8000-8500mah.
That would make for a great flashlight battery. 
As far as I understand, neither Shockli, nor PLB really have their own developments, and if they have a real production in which they work with the very stuffing of their batteries (and not just engaged in dressing the outer shell under their name), then this most of the stuffing they take already finished form from someone from the largest manufacturers. Maybe, then one, then the other, then the third or fourth. And then there is some mysterious fifth national Chinese manufacturer, which supplies its most important stuffing under the name “INR26650-50A” and “INR26650-55A” for most of the elements, for example, for the manufacturer of PLB, LiitoKala, and many many other nameless. To make sure of this, you just carefully look at the market, where most of them even do not want to change the shell of the basic “INR26650-50-55A”, because it also costs money. Only some of the sellers decide to make a cheap sticker on the surface of these “INR26650”, for example, as does LiitoKala. They do not even hesitate to say loudly about the discharge current = 20A, and indicate only 15A for confidence. At the same time, they made an “update”, instead of 5000mAh, they now write 5100mAh )) 5100mAh
What about the size of 26980 can I say? These are elements that are based on the same “INR26650” filling, only the size of its internal roll is increased. Yes, they really should be better, but everything is relative. Better than what? This very “national Chinese basic” stuffing perfectly does only some then one manufacturer (the fifth one, unknown to most of us). But, since this filling is the national treasure of China, other manufacturers of batteries for batteries also have the right to make it. That is, make copies of it. I think that it is impossible to acquire the original stuffing, because it goes for the military needs of China. Therefore, such manufacturers sellers like Shockli, LiitoKala and hundreds of others can only choose between copies of the INR26650 filling. Someone chose a better manufacturer, someone worse, but in the end, according to the graphs of our esteemed HKJ, you can see that many of the elements have a very similar character of their bit characteristics. With only minor differences. And this is normal, because it is impossible to make absolutely identical copies in everything.
Shockli, for example (4300-Green), has a very noticeable problem at the beginning of the start at high currents, after which a pendant bag suddenly appears at the line, which then rises back to the main discharge line ( https://i.imgur.com/SKWqUWC.png ). This is a very big disadvantage because the reverse lift only seems like a good thing. In fact, it is due to the rapid heating of the element and the reduction of internal resistance in just such a negative way. This will affect the resource, which will be much lower than those of elements for which this effect is not observed. Another way out is it is not to shock Shockli with large currents in order to avoid such sagging at the start in the form of a temporary bag. And can anyone say why HKJ never showed its own measured data on the internal resistance of the still cold (before connecting any loads) Shockli-5500? - “Calculated internal resistance (ohm) - xxxx (ohm)” ??..
Samsung T-30 3000mAh original - today you can not buy it. Only original fakes (no letters in the title “TB” and with slightly different sizes from the original) Sammmmsung T-30
Well, or here is such a frank trash (apparently, also with a familiar filling of the type “INR26650-50 \ 55”) 21700 T30 
Golisi-4300 S43 Gold… the lowest price? 
QB26650 INR26650 5000mAh 3.7V 20A :question:
As far as I know, Power Long Battery and Shenzhen Yongde Lixin Energy are cell manufacturers. Their official specifications do not necessarily follow the usual standards of the main manufacturers LG, Murata/Sony Panasonic/Sanyo or Samsung. Power Long Battery, for example, states/specifies 1C discharge rate, a lot higher than the usual 0.2C.
With regards to discharge rates there is no standard. Chinese manufacturers like to specify borderline high continuous figures which straight make cells overheat. Samsung endorses cycle life and is usually cautious, whereas Murata/Sony is aggressive and does not hesitate to list maximum continuous discharge ratings which may require temperature cut-off.
They can write whatever they like. Among top bad and completely good there are rewrappers of all kinds.
Some of the latest reviews of that seller are dubious. You may find other similar sales.
LOL!
Looks like Samsung 30T cells, if the seller is trustworthy that is.
That looks to be the same Lishen manufactured cell used by LiitoKala in their Lii-40A rewrap. Actual specifications are 4000mAh capacity and 3C maximum recommended continuous discharge rate (12A).
Looks like a nice price. :THUMBS-UP:
¯\_(ツ)_/¯
Cheers :-)
Now add to them also those salespeople that I showed you along with the links in the posts above. Then you will also find a whole bunch of exactly the same, just lesser known “PLB”. And they all have their own personal production with a turnover of about two million batteries per year, including completely identical versions of the “INR26650-50A and INR26650-55A. Even the shell is almost the same for everyone, but they all say that they make these elements independently in their own production. Often, even the characteristics with the description for these INR26650 are made as a copy. And this is true, because the main source of material for all is the same and structurally they are all twins.
The question is only one, the final product of which in the end turns out better. Shockli chose PLB manufacturer. And another of his competitors chose the neighboring manufacturer INR26650. Or also signed a contract with the same PLB, who knows them for sure. Items for ”Shockli-5500” bought from PLB. But, for the “Shockli-5250”, apparently they have now been selected from some other kindred PLB. Look, despite the number of the approximate value of mAh and the high current usage of both models 5500 and 5250, the graphs of their unloading noticeably differ from each other. In general, if you can order items directly from PLB itself, then why search for Shockli objects, overpaying for a simple new label, which inside the battery will still not be visible? In addition, there are suspicions that when buying batteries in order to reduce costs, Shockli asks the manufacturer not only for the absence of a factory label, but also prefers to place an order with a cheaper protective membrane (disables the contact of the element during an overload). That is why on the graphs we see a sharp drop under load at the very beginning of a more or less noticeable discharge in the form of a bag hanging down and then rising back, and even higher than the former.
This is the effect of poor contact of the protective plate, because of which it quickly overheats and only after this heating has good conductivity. This is reflected in the subsequent rise of the discharge line on the graphs after its entry into the bag. At the same time, completely unnecessary heating of chemistry occurs in the region of this membrane, which adversely affects the resource and durability. And such elements cannot be connected to a battery with a large number of cells at all, since they very quickly lose the balance of voltage and mAh. The usual internal BMS with its small balancing currents can not cope here.
In short, these are individual power sources, which are suitable only for smoking cigarettes, that is, they will be there good for what they are intended. And for different flashlights. For good such powerful flashlights, they also fit perfectly