The Battery Tender 12V 800mA Weather Resistant charger is a permanently mountable maintainer for 12-volt lead-acid batteries. The manufacturer says it carries the same four-stage ISM charging, float maintenance, spark-proof connections, and reverse polarity protection as the standard Junior, packaged in a hardened housing for outdoor batteries. Its 800mA output suits long-term maintenance charging of motorcycle, ATV, and powersport batteries over winter storage.
Compared with an indoor-only charger, this model is IP67-rated, so it can stay connected through rain, snow, and humidity in a carport, shed, or dock. The manufacturer also includes the hardware for a fixed installation, so you can mount it once and reconnect each season instead of relocating it every time. The 3-year limited warranty and ETL/CETL listing give buyers a documented standard to weigh against cheaper, unrated trickle chargers, and the price is justified mainly by outdoor durability and not having to replace a dead battery.
The manufacturer lists use on ATVs, personal watercraft, motorcycles, boats, side-by-sides, and dirt bikes, and it is rated for flooded, AGM, gel, and sealed maintenance-free lead-acid batteries. For a permanent setup, the manufacturer's install guidance favors the ring terminal harness, which attaches to the battery posts with 8mm and 10mm wrenches, and it recommends dielectric grease on the connections. Owners on user forums report mounting these under a carport or in an engine bay, but the manual cautions against exposing the unit to rain, so confirm placement with the manufacturer.
The manufacturer rates the unit IP67 and says it is designed to remain connected through rain, humidity, and freezing temperatures. Owners on user forums report outdoor use, but the manual advises against exposing the unit to rain, so details vary. Confirm the intended placement with the manufacturer before a permanent outdoor install.
The manufacturer's listed battery types for this model are flooded, AGM, gel cell, and sealed maintenance-free lead-acid. Lithium compatibility was not confirmed for this part number, so check with the manufacturer before connecting it to a lithium battery.
The manufacturer includes a two-in-one cable with alligator clips and a ring terminal harness, along with an instruction manual.
For a permanent install, the manufacturer's guidance uses the ring terminal harness: identify the positive and negative battery posts, bolt the ring terminals on with 8mm and 10mm wrenches or a socket set, and apply dielectric grease to the connections. Mount the charger in a dry, sturdy spot away from heat and moving parts, then plug the AC cord into a standard 120V outlet. Alligator clips work for one-time sessions but are less secure for seasonal storage. Check the polarity before connecting, since reverse polarity protection is a safeguard, not a substitute for correct wiring.
