Klein Tools KTB2 Portable Jobsite Rechargeable Battery, 13400mAh

The KTB2 is built for the trades: rugged chassis with an IP65 rating, so it shrugs off dust and water jets on an open site. Body is plastic and metal, and there's a built-in stand so it props up on a bench or in a panel bay. One thing to respect - Klein says don't subject it to vibration, impacts or drops, so IP65 covers weather and dust, not being run over by a scissor lift.

Yes, the KTB2 has both a USB Type-A and a USB Type-C output and can run them together up to 28W total. The Type-A port peaks at 12.5W with Qualcomm Quick Charge 3.0, and the Type-C does up to 15 watts. Auto-device detection sorts out what each device wants. If you pull both at once you're sharing that 28W ceiling, so two devices charge slower than one.

Operating range on the KTB2 is 32 to 104 degrees F (0 to 40 C). That rules out freezing crawlspaces, unheated winter job trailers, and a hot attic in July, which regularly runs past 104. Keep it in the van or on your belt rather than leaving it staged in an unconditioned space overnight.

No. Maximum output is 28W total across a USB-A and a USB-C port, with 15 watts the ceiling on the Type-C. That covers phones, tablets, headlamps, test instruments and a Bluetooth speaker. It will not run a power tool, and Klein explicitly warns against loading it past its output rating, since overload risks fire or injury. For anything drawing real amperage you need a proper jobsite power station, not a USB power bank.

Recharge runs 4 to 10 hours depending on how much wall adapter you feed it. The input is USB Type-C, and a USB Type-C to USB Type-A cable comes in the box, so you can charge it off any standard USB-A wall block or a truck adapter without buying anything else. Klein warns against using a charger or cable not recommended by the manufacturer.

The KTB2 rates at 48 Wh single cell equivalent capacity, which is the number airlines actually go by rather than the 13400mAh figure. It's a lithium-ion pack built from four 18650 cells. Check your carrier's current rule against that 48 Wh number before you fly with it.

There's an integrated LED work light with two levels: 170 lumens on high and 100 lumens on low. That's task-light territory for reading terminal markings inside a panel or a junction box, not area lighting for a room. The built-in stand lets you aim it and keep both hands free.

Charge it every 3 months. Lithium-ion packs left flat for long stretches degrade, so a spare that lives in a service truck or a stocked MRO cage needs putting on a quarterly rotation. It won't self-charge, either, since it isn't solar compatible.

Rated at 300 cycles. For a tech who tops it off every workday, that's roughly a year of daily use before capacity starts falling off noticeably. Fleet buyers standardizing across a crew should budget on that basis rather than treating it as a permanent tool.

Total product weight is 10.5 oz (300 g), with the battery itself accounting for 6.4 oz (180 g). Dimensions are 5.7 x 3.5 x 1 inches. That's pocketable in a bag pocket or a tool pouch, though it's heavier than a phone, so most techs stage it in the pouch rather than a shirt pocket.

One battery per unit, model KTB2, supplied with a USB Type-C to USB Type-A cable. There's no swappable spare pack, the cells are sealed inside and there are no user-serviceable parts, so a crew wanting a backup buys a second unit.