Verify the trimmer after maintenance ID: lst300-after-care Version: 2.0.0 Model: BLACK+DECKER LST300 · US · AF-100 Region: US Parts: Automatic-feed head with AF-100 spool; match model and tool type to manual Not covered: LST420 / LSTE525; GH corded models; Dual-line heads; Metal line or blades; Nonmatching tool type or modified head; Unknown tool type or missing exact-type manual; Bump-feed conversion MATCH YOUR VERSION Model and tool type: LST300 and the exact type on my label match my manufacturer manual and figures Remove the battery before finding the label. Use the manufacturer model-and-type lookup; this site does not infer a type number from LST300 alone. Cutting head: Original AF-100 automatic-feed single-line head Do not substitute a bump-feed procedure, dual-line spool or metal cutting attachment. PREPARE [ ] Release the trigger, let the head stop, engage the lock-off and remove the battery. Leave it removed throughout hands-on care. Keep fingers away from the sharp cutter on the guard. [ ] Read LST300 and the tool type from the label. Open the official model/type lookup and compare its manual and parts figures with your actual guard, single-line head and AF-100 spool. A readable model name alone does not establish the type. If the exact type manual cannot be obtained, or any figure differs, save a preparation record and stop. [ ] Tool: Manual-specified eye and hearing protection [ ] Tool: Substantial footwear and suitable outdoor clothing [ ] Material: No replacement material needed for an intact tool STOP Keep the battery removed if the exact type/manual match is unknown or parts differ from the figures. Stop for a damaged battery, exposed wiring, a faulty switch, cracked guard, broken spool/hub, damaged cap tabs or housing slots. Use an authorized service center. Never open the battery, motor housing or charger. CONSUMABLE FIT CHECK ROUTE safety: Is the battery removed, the trigger released and the cutting head stopped, with no battery damage, exposed wiring or faulty switch? Yes -> compatibility: Keep the battery removed for every hands-on step. No -> service: Stop using the tool for electrical, battery or switch damage. If you have only omitted battery removal, make the tool safe before restarting. Not sure -> prepared: Keep the battery removed. Save your preparation record and check the matching manual before continuing. compatibility: Have you matched the label LST300 AND its exact tool type to the official lookup manual and its figures, with the original AF-100 automatic single-line head? Yes -> check-1: Record the label type and matching manual reference in the first step. No -> prepared: An unknown type, unavailable type manual, different figures, bump-feed head or dual-line conversion blocks this procedure. Use manufacturer support to identify the correct instructions. Not sure -> prepared: Keep the battery removed. Save your preparation record and check the matching manual before continuing. check-1: Are the guard, cap, handle and collar secure, with correct line and no damaged part? Yes -> check-2: Prepare the operating area only after these checks pass. No -> service: Leave the battery out until any missing or damaged retention part has been resolved. Not sure -> prepared: Keep the battery removed. Save your preparation record and check the matching manual before continuing. check-2: Can you arrange a dry outdoor area, required protection and the manual’s bystander clearance? Yes -> steps: Normal-use testing is optional; record untested if the area is not yet ready. No -> prepared: Complete the unpowered preparation and arrange a safe area before any retest. Not sure -> prepared: Keep the battery removed. Save your preparation record and check the matching manual before continuing. CARE STEPS (only when the route reaches steps) [ ] 1. Record the exact tool and make it safe Release the trigger, let the head stop, engage the lock-off and remove the battery. Leave it removed throughout hands-on care. Keep fingers away from the sharp cutter on the guard. Read LST300 and the tool type from the label. Open the official model/type lookup and compare its manual and parts figures with your actual guard, single-line head and AF-100 spool. A readable model name alone does not establish the type. If the exact type manual cannot be obtained, or any figure differs, save a preparation record and stop. Look for: The battery is physically separate from the tool; your label type and matching manual reference are written below. Source: bd-manual-help, Official model/type lookup instructions; type is beside or below the model number [ ] 2. Check the completed assembly with power removed Check the guard screw, both cap tabs, auxiliary handle and tightened height collar. Confirm round 0.065 inch (1.65 mm) nylon exits the eyelet and reaches no farther than the guard cutter. Look for: Every user-adjusted part is secure and no line is trapped under the cap. Source: lst300-manual, English pp9–10 Replacing the spool; figs M–O [ ] 3. Prepare the normal working area Clear wire, cord and loose objects from a dry outdoor area. Wear the manual’s required eye and hearing protection, long pants and substantial footwear. Keep people and pets away; edging requires at least 100 feet (30 m) clearance. Look for: The ground and area are suitable for normal trimming, with clear separation from bystanders. Source: lst300-manual, English pp2–3 Safety; p8 Installing and removing the battery pack [ ] 4. Choose whether to run a normal-use check You may leave the battery out and record untested. To check operation, only after assembly and area checks pass, insert the undamaged matching battery fully until latched. Keep eye protection on whenever the pack is installed. Look for: Your record will distinguish an unpowered check from an observed running result. Source: lst300-manual, English pp2–3 Safety; p8 Installing and removing the battery pack [ ] 5. Observe normal control and feed If testing, follow the manual stance and normal lock-off/trigger controls. Keep the guard at least 24 inches (609.6 mm) from your feet, cut with the line tip and never bump the head. Stop if feed fails, running is slow or vibration is abnormal. Look for: Record only what you observe during ordinary use; no hands approach the rotating head. Source: lst300-manual, English pp8–9 Height adjustment / Operating the trimmer; figs I, J1 [ ] 6. Stop before any further inspection Release the trigger and wait for the head to stop. Remove the battery before touching the cap, guard or line again. A trigger that cannot switch the tool off requires service; keep clear of moving parts and do not handle the head. Look for: The head has stopped and the battery is removed before hands-on inspection resumes. Source: lst300-manual, English pp2–3 Safety; p8 Installing and removing the battery pack [ ] 7. Record an observed or untested result Choose normal operation observed, symptom remains, or powered check not performed. Record any remaining symptom for support. If feed or slow running persists after the corresponding user checks, leave the tool unused and contact service. Look for: The result accurately describes whether the normal-use check happened and what it showed. Source: lst300-manual, English pp10–11 Automatic line feed does not work; figs N, Q, R OBSERVATIONS Tool type exactly as printed on the label (required): ____________________ Exact-type manual reference or link that you matched (required): ____________________ Normal-use observation (required): ____________________ Choices: Normal control and feed observed / Symptom remains; leave unused [service required] / Powered check not performed [further care/preparation needed] Remaining symptom or next action (required): ____________________ Result of this task (required): ____________________ Choices: Checks passed; ready for the stated next step / More preparation or a linked task is needed [further care/preparation needed] / Leave unused and contact service [service required] RESULT CHECKS [ ] All unpowered retention and line checks pass before the battery is installed. [ ] The result explicitly states observed normal operation, a remaining symptom, or an unperformed powered check. NEXT CARE After user maintenance, spool replacement or adjustment Verify assembly after each care task and before returning to normal use. Basis: manufacturer Source: lst300-manual, English pp2–3 Safety; p8 Installing and removing the battery pack Record preparation, maintenance readiness, problem located or service needed. This is not proof of a physical repair. SOURCES BLACK+DECKER LST300 instruction manual (manufacturer document, retailer-hosted) https://pdf.lowes.com/productdocuments/1935f26b-7448-4c95-b467-a223bb73d80f/63056925.pdf English pp8–10 Assembly, Operating instructions, Replacing the spool; pp2–3 Safety Checked: 2026-10-13 Manufacturer copyright, hosted by Lowe’s. Facts paraphrased; no diagrams or manual redistributed. BLACK+DECKER: locate a manual using model and type number https://support.blackanddecker.com/hc/en-us/articles/360012700118-How-can-I-get-a-parts-list-or-manual-for-my-tool Official model/type lookup instructions; type is beside or below the model number Checked: 2026-10-13 Linked only. BLACK+DECKER LST300 product and support https://www.blackanddecker.com/products/lst300 LST300 model identity; Automatic Feed Spool; Includes AF-100 Checked: 2026-10-13 Linked only; no product photos reused.