Browse all models →DOCUMENTATION-BASED PRODUCT REVIEW
Model: MD321 (manual table also lists A306; verify product label)
A full-size Amazon model with a 53.15-inch SL-track, automatic footrest extension and a documented 300-pound capacity.
Research by the Recline Guide Editorial Team · Documentation last reviewed August 29, 2026 · Amazon availability can change
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QUICK SPECIFICATIONS
Source checked: Amazon-linked MassaMAX MD321 manual. Specifications may change by revision or seller bundle; match the model name and product label before purchasing.
DETAILED OVERVIEW
The MassaMAX MD321 combines a 3D mechanism with a 53.15-inch SL-track, automatic body scan, 12 automatic programs, full-body air compression, foot rollers, back and calf heat, yoga stretching, and zero-gravity recline.
Its clearest buying specifications are a 300-pound maximum, 7.9-inch automatic footrest extension, 1.98-inch rear gap, and three-year warranty for quality defects. The main uncertainty is fit: the source does not publish a recommended user-height range or complete reclined dimensions.
WHO IT SUITS
FEATURE ANALYSIS
The 3D mechanism adds adjustable in/out pressure while the long SL-track continues beneath the seat. Automatic scanning helps place the massage, but the absence of a height range still matters.
The leg rest extends automatically by 7.9 inches. Sole rollers, calf compression, and back/calf heat create distinct lower-body features rather than one generic “full-body” function.
FIT AND ROOM PLANNING
The published 300-pound maximum is useful, but no height range is stated. The 7.9-inch footrest extension suggests flexibility for longer legs, not proof that a specific tall user will fit the shoulder scan and seat.
The chair is 61.02 × 29.53 × 45.08 inches upright and needs 1.98 inches behind it. Full reclined dimensions and carton measurements are not published in the extracted manual.
Check the room-fit calculator →ADVANTAGES
LIMITATIONS
DELIVERY AND SETUP
205 lb chair; confirm carton size and service level with seller. The chair weight is 205 lb, and the setup guidance is: Assembly required; two people recommended. Measure every doorway, turn, stair, and landing; confirm whether delivery is curbside, threshold, room-of-choice, or white glove.
WARRANTY AND SUPPORT
The Amazon-linked manual states a 3-year warranty for quality defects. It does not break out labor, parts, structure, or in-home service in the extracted text.
The manual lists MassaMAX customer service at 866-909-6062 and directs Amazon purchasers to seller support.
NOT RELIABLY VERIFIED
BEFORE YOU ORDER
Confirm the exact model name, Amazon product ID B09HH1H3RM, selected color or configuration, seller, warranty administrator, delivery service and return-freight responsibility on the checkout page. Save a copy of the listing and warranty shown when you order.
For fit, compare every intended user with the published height and load limits above. For delivery, measure the packaged route—not only the assembled chair—and include door trim, turns, stairs, landings and elevators.
SIMILAR CHAIRS TO CONSIDER
PRODUCT-SPECIFIC FAQ
Not published; automatic footrest extends 7.9 in
300 lb
1.98 in rear
Yes. Zero-gravity recline is documented, but the number of distinct positions is not stated in the source used here.
Foot rollers and 7.9-inch auto-extending footrest
Back and calf heat
Assembly required; two people recommended
53.15-inch SL-track. Yes. Automatic body scan is documented.
LEARN BEFORE YOU BUY