Promate Universal 20000mAh Ultra-Slim Power Bank with 20W USB-C Input/Output Port, QC 3.0 Output, USB-C Ports, LCD Display and Over-Heating Protection for Smartphones and Tablets - Blue / BOLT-20PD.BLUE / BOLT-20PD.BLUE

The Promate BOLT-20PD in blue is a universal 20000mAh power bank with a 20W USB-C input and output port, Quick Charge 3.0 output, an LCD display and over-heating protection. It is specified for smartphones and tablets, and the ultra-slim body is what keeps a pack of this capacity carryable rather than luggage.

The USB-C port supplies 20W, the level current phones use for their fastest charging. At that rate a short stop moves a phone a long way instead of adding a few percent, which is the difference that matters when you are charging between meetings rather than overnight.

A QC 3.0 output sits next to the USB-C port for devices that negotiate over Quick Charge rather than USB Power Delivery. Carrying both standards is what makes the BOLT-20PD universal in practice, since which protocol a phone uses is fixed by its chipset and not by the cable in your bag.

That same 20W USB-C port takes input as well, so the bank recharges through the connector it charges from. On a 20000mAh pack the input rate is what stops a refill from occupying an entire night and part of the next morning, which is a real constraint on large-capacity banks.

An LCD display shows the pack's charge as a number rather than a row of dots. On a bank this large that reading is what makes the capacity usable, because four indicator lights cannot tell you whether there is enough left for a tablet or only for a phone.

Over-heating protection watches the pack while it charges and discharges. Heat is the failure mode that matters most on a high-capacity lithium cell, and protection circuitry is the part of a power bank you never see working, which is precisely why it belongs on the specification list.

Promate builds this pack ultra slim, which is the notable claim at 20000mAh. Capacity normally shows up as thickness, and the slim profile is what decides whether a bank slides into a laptop sleeve or claims a corner of the bag entirely to itself.

The BOLT-20PD is specified for smartphones and tablets, which is where 20000mAh earns its keep. A tablet takes a serious share of any pack, so a bank able to refill one and still hold capacity for a phone is the sensible minimum when both travel together.

This version wears a blue finish, which makes it easier to identify at a table or in a bag than another black brick. Promate describes the pack as universal, with USB-C and Quick Charge outputs covering the mix of devices most people actually carry rather than one ecosystem.