The best low-and-slow accessories for a Weber Smokey Mountain are an accurate dual-probe digital thermometer, a chimney starter for lighting coals Minion-style, and — if you want truly hands-off cooks — a fan-driven temperature controller mounted with a WSM lower-vent adapter. With those three covered, extras like gasket kits, rib racks, and water-pan mods simply refine an already excellent smoker.

That's the honest answer, and it's a short list because the WSM needs so little help. Here's why — and how to spend your money in the right order.

Why is the WSM already great at low-and-slow?

The Weber Smokey Mountain is a bullet-shaped water smoker: a porcelain-enameled steel body with a charcoal ring at the base, a water pan that acts as a heat sink, and two cooking grates stacked above it. It comes in three sizes — the 14.5" (286 square inches of cooking space), the 18.5" (481 square inches), and the 22.5" (726 square inches) — and airflow is managed with three bottom vents plus a single top vent.

Once you learn the vents, a WSM will hold 225–250°F for hours with almost no fuss. So the point of accessories isn't to fix the smoker — it's to remove the two remaining chores: measuring grate temperature accurately and babysitting airflow on long cooks.

Which accessories actually matter for low-and-slow?

In order of impact:

Do you need a separate thermometer for a WSM?

Yes — it's the single most important upgrade. The stock lid thermometer measures air up at the dome, which commonly runs 15–25°F hotter than grate level on a bullet smoker. Since every low-and-slow target — 225°F for brisket, 250°F for ribs — refers to the air at grate level, you're flying blind without a probe clipped where the food actually sits.

A dual-probe (or multi-probe) leave-in thermometer handles both jobs at once: one probe on the grate for pit temp, one in the thickest part of the meat for internal temp. You'll see