Installing and Removing the Battery Pack

WARNING: Make certain the lock-off button is engaged to prevent switch actuation before removing or installing battery.

To install battery pack:

Insert battery pack (2) firmly into trimmer until an audible click is heard as shown in figure C. Ensure battery pack is fully seated and fully latched into position.

To remove battery pack: Depress the battery release button in the back of the battery pack and pull battery pack out of trimmer.

This product can accept any of the batteries and chargers listed in the chart below.

LI-ION Battery Packs and Chargers


Description	Cat. #
Batteries: LI-ION	LBX20
	LBXR20
	LBXR2020
	LB2X4020
Chargers: LI-ION	LCS1620
	L2AFCBST
	L2AFC

ASSEMBLY and Adjustment

installing the guard

WARNING: remove the battery before attempting to attach the guard, edge guide or handle. NEVER OPERATE TRIMMER WITHOUT GUARD FIRMLY IN PLACE. The guard must always be on the TRIMMER to protect the user.

• Turn the trimmer upside down so that you are looking down at the spool cap (9).

• Remove the screw from the guard with a phillips screwdriver.

• Turn the guard (8) upside down and slide it fully onto the motor housing (6). Make sure the tabs (10) on the guard engage the ribs (11) on the motor housing as shown in figure D. The locking tab (25) should have snapped into the housing slot (26).

• Continue to slide the guard on until you hear it “snap” into place.

• Using a phillips screwdriver, insert the guard screw as shown in figure E to complete the guard assembly.

• Once the guard is installed, remove the covering from the line cut-off blade, located on the edge of the guard.

Attaching the Auxiliary Handle (FIGURES F & G)

• Push the auxiliary handle (3) onto the tube (10).

• Slide the bolt (11) into the hex-shaped hole of the handle and through to the opposite side.

• Tighten the knob (12) onto the bolt by turning it clockwise.

Adjusting the position of the auxilIary handle

The auxiliary handle can be adjusted to provide optimum balance and comfort.

• Loosen the knob (12) on the bolt (11) by turning it counter clockwise.

• Gently slide the auxiliary handle up or down the tube (10) to the desired height.

• Tighten the knob onto the bolt by turning it clockwise.

Adjusting the height of the TRIMMER (FIGURE H)

CAUTION: Adjust the length of the trimmer to obtain proper working positions as shown in figure I1.

This trimmer has a telescopic mechanism, allowing you to set it to a comfortable height. To adjust the height setting (figure H):

• Release the height adjust locking clamp (5).

• Gently pull the tube (10) up or down to the desired height.

• Close the height adjust locking clamp.

LST400R, LST400, LST420R, LST420 specifications

Black & Decker is recognized for producing high-quality outdoor power tools, and their string trimmers, particularly the LST420, LST420R, LST400, and LST400R models, are exemplary of their innovation and commitment to efficiency. These cordless electric trimmers combine robust performance with user-friendly features, catering to both novice and experienced gardeners.

The LST420 and LST420R models feature a powerful 40V lithium-ion battery, ensuring extended run times and plenty of cutting power. Both models utilize a premium 12-inch cutting width, allowing users to trim and edge grass and weeds efficiently. Weighing in at around 6.5 pounds, these trimmers are lightweight, making them easy to maneuver and reducing user fatigue during extended periods of use.

One of the standout features of the LST420 and LST420R is the automatic feed spool, which continuously feeds the line when needed, eliminating interruptions during work. Furthermore, users can easily switch between trimming and edging modes with a simple turn of the shaft, thanks to the innovative pivoting head design. This feature enhances versatility, allowing users to achieve a professional finish on various landscaping tasks.

The LST400 and LST400R also sport the reliable 40V lithium-ion battery and 12-inch cutting width. However, these models feature a slightly different design. The LST400 is designed with a telescoping shaft that can be adjusted for different heights, offering added comfort and control for users of varying statures. With the addition of a secondary handle, it provides improved stability during operation.

All four models boast a relatively quiet operation compared to gas-powered trimmers, which adds convenience to residential areas while minimizing noise pollution. The efficient brushless motor technology found in these trimmers enhances durability and runtime, further highlighting Black & Decker's commitment to sustainability and user convenience.

In summary, the Black & Decker LST420, LST420R, LST400, and LST400R offer a blend of power, versatility, and user-friendly features. With their lightweight designs, automatic feed spooling, adjustable shafts, and efficient battery systems, they are ideal choices for maintaining a neat and tidy lawn while ensuring comfort and ease of use for the operator. These trimmers embody the brand's dedication to quality and innovation in outdoor power tools, making them a reliable choice for homeowners and gardening enthusiasts alike.