Ninja DoubleStack XL SL401, Deep Grey

What the SL401 is and what is in the box

The SL401 is Ninja's DoubleStack XL: two 5-quart baskets stacked one above the other in a single housing, for 10 quarts in total. Zone 1 is the top basket and Zone 2 the bottom, each with its own heating element and fan according to the owner's guide. SharkNinja's page lists 120 volts, 1,690 watts, a 15-amp rating, a 32-inch cord and a one-year warranty.

The box holds the air fryer, two 5-quart baskets, two nonstick crisper plates and two stacked meal racks, plus recipes. SharkNinja's page and the Amazon bullet say 20 recipes, while one Amazon details field says 10. The meal racks let you cook on two levels inside each basket, which is how the listing arrives at four foods at once.

There are six programs: Air Fry, Air Broil, Roast, Bake, Reheat and Dehydrate. The listing and SharkNinja's page both say it fits two 5-pound chickens at once and can feed up to 8 people; SharkNinja's page adds 5 pounds of wings in each drawer.

Size, and the 6-inch clearance in the guide

SharkNinja gives the size as 20.83 inches long, 13.07 wide and 17.72 high, and the weight as 25.13 pounds. Amazon lists 11.25 deep by 19.22 wide by 15.14 high and 24.3 to 24.4 pounds. The two sets of dimensions do not match, so measure your space against SharkNinja's larger figures.

The Amazon bullets say the stacked design still fits under standard cabinets. The owner's guide adds a condition in its troubleshooting section: if the display shows O-H, the unit is overheating because it is in a corner or constricted space, and it requires at least 6 inches of space on the top and sides for air circulation. Neither source gives a cabinet height, so check your own clearance above the unit.

Placement rules in the safeguards: use it on a worktop only, not near the edge, and do not move it while in use. Nothing should be placed on top during use, and the air intake and outlet must not be covered; the parts diagram shows the air outlet on the side of the unit.

Power: no extension cord, no low outlet

The guide's safeguards say do not use an extension cord and never use a socket below counter level. They also say not to connect the air fryer to an external timer switch or separate remote-control system. SharkNinja's page rates it at 15 amps and 1,690 watts.

The Amazon details field lists 230 volts and a 40 to 240°C range. SharkNinja's page and the owner's guide both say 120 volts, 60 Hz. The listing field does not match either maker document, so ask the seller to confirm before buying if the listing's figure concerns you.

Zones, Smart Finish and the timer rules

The control panel has Smart Finish, which uses a HOLD mode so both zones can finish together, and Match Cook. A separate Double Stack Pro button is used for cooking with the stacked meal racks, which is how the listing arrives at four foods at once.

The guide says no preheat is needed. Pulling a basket out pauses its timer; reinsert it within 10 minutes or that cook is cancelled. After 10 minutes with no interaction, the unit goes into standby. To remove food, the guide says to tip it out or use silicone-tipped tongs and never to set the baskets on top of the unit.

Function defaults from the guide: Air Fry 390°F; Air Broil fixed at 450°F with no temperature adjustment; Bake 325°F for up to 4 hours; Dehydrate 140°F for 1 to 12 hours; Reheat 250°F for up to 1 hour. The Roast page lists a 250°F default and up to 1 hour but its steps repeat the Reheat wording, so confirm Roast settings with SharkNinja.

Cleaning: which parts can go in the dishwasher

The guide says the baskets, crisper plates and stacked meal racks are the only dishwasher-safe parts, and that hand washing them will extend their life. The main unit should only be wiped with a damp cloth and must never be immersed or put in a dishwasher. The listing's dishwasher-safe crisper plate claim agrees with this.

The baskets and crisper plates get extremely hot, so the guide asks you to set them on a heat-resistant surface, not straight onto a counter, and never to place the baskets on top of the unit itself.

Warranty: one year, and what it excludes

SharkNinja's page lists a one-year warranty. The guide's terms apply to the original owner, for purchases from authorized retailers, under normal household use. SharkNinja repairs or replaces defective units at its discretion, and a replacement unit is covered for six months from receipt or the rest of the original term, whichever is later.

Wear parts such as racks and pans are excluded, along with commercial use, misuse, repairs by people SharkNinja has not authorized, and products used outside North America. Claims start with a phone call and the receipt. SharkNinja pays to have the unit sent in but charges a return-shipping fee, stated in the guide, when it ships the repaired or replacement unit back.