Our take
Sharp's operation manual gives a clear identity and installation path for R-420LW. It maps the W suffix to white and names white built-in kit RK-40W24 for this exact model, while the same document says the oven can stand on a counter with at least two inches of clearance at each side, above and behind. The specifications list 1.4 cu. ft., 1,100-W IEC output, separate 1,600-W / 13.5-A electrical input, 120 V / 60 Hz and a 14 1/8-inch turntable. Sensor cook/reheat and keep-warm functions are also documented. The R-420LW remains distinct from black R-420LK and the larger R-420D generation.
A white 1.4-cu.-ft. household model for users who want sensor functions and a documented countertop or matching trim-kit route..
Avoid this model if you need a cavity larger than 1.4 cu. ft., a kit-free cabinet installation, or a stainless or black finish.
Pros & cons
What could work for you, and what to consider before buying.
What works in its favor
- The manual ties the W suffix to white and maps the exact RK-40W24 optional kit.
- Output and electrical input are listed separately with 120-V / 60-Hz supply.
- The documented 14 1/8-in. turntable and sensor programs help evaluate dish and control needs.
What to weigh up
- The 1.4-cu.-ft. cavity may not suit larger cookware or family-size dishes.
- The built-in route requires a separate, exact model kit and its cabinet-opening instructions.
- The historical Amazon ASIN is not confirmed as a current exact offer.
The key details
| Model covered | R-420LW |
|---|---|
| Capacity | 1.4 cu. ft.; Sharp's manual lists outside dimensions 21 5/8 × 12 3/8 × 17 1/2 in. |
| Microwave output | 1,100 W IEC microwave output; manual separately lists 1,600 W / 13.5 A input |
| Cooking approach | Sensor cook/reheat, auto-defrost and keep-warm functions are documented in the model manual |
| Installation options | Countertop clearance is specified; optional white kit RK-40W24 is mapped to R-420LW |
| Finish and turntable | White R-420LW variant with a 14 1/8-in. turntable |
Performance figures are manufacturer claims. Source checked October 10, 2026. Regional models and included accessories can differ.
What the features mean for you
Read R-420LW as the white finish code
Sharp's shared R-420L/R-425L manual states that the final letter identifies color: K is black, S stainless and W white. It specifically maps white kit RK-40W24 to R-420LW, while the black R-420LK uses RK-40K24 and the stainless kit named in the manual belongs to R-425LS. This is a useful suffix boundary when older listings omit letters or use family-level photos. Keep the exact R-420LW identity in product and accessory checks; a visually similar R-420L or R-425L entry is not automatically the same trim or cabinet kit.
Check the 1.4-cu.-ft. cavity and 14 1/8-inch tray
The manual gives 1.4 cu. ft. of oven capacity and a 14 1/8-inch turntable, with outside measurements of 21 5/8 inches wide, 12 3/8 inches high and 17 1/2 inches deep. The tray diameter gives a better starting point for round plates than cavity volume alone, but the dish still needs side clearance to rotate. Rectangular dishes also need to fit across the cavity without touching the walls. Measure the microwave location and everyday cookware, and leave required airflow around the housing. These documented dimensions make the Sharp a mid-size alternative to Panasonic NN-SN65KB's 1.2-cu.-ft. model.
Use the manual's sensor programs with their stated limits
The operation manual describes sensor cook, sensor reheat and keep-warm options, giving the R-420LW more guided operation than a basic time-only oven. These functions can simplify supported tasks, but a program name does not guarantee a particular result for every food amount or container. Follow the manual's specific food directions and check cooking partway through when the guide recommends it. Sensor cooking is a separate attribute from ordinary touch controls or preset keys, so the profile records it only because the manual identifies sensor functions. Users who prefer manual timing can still compare the listed power levels and defrost controls.
Keep output separate from electrical input
Sharp reports 1,100 watts of output under the IEC test procedure and separately lists 1,600 watts / 13.5 amps of AC power required. The output figure belongs in cooking-power comparisons; input and amperage inform electrical planning. The manual specifies single-phase 120 V / 60 Hz AC and recommends a separate circuit. Verify the branch circuit, grounded receptacle and unit plate before installation. These published specifications do not measure the speed of a particular recipe, and they do not replace local electrical requirements. The separate figures are more informative than listings that use one unlabeled wattage number.
Choose between counter clearance and the exact cabinet kit
For counter use, Sharp asks for at least two inches on the sides, top and rear for air circulation, and warns against placement near heat and steam. It separately documents cabinet or wall use with white built-in kit RK-40W24 for R-420LW. The kit is optional; the product page does not imply it is included. A cabinet plan therefore needs both the exact kit code and the required opening dimensions. Do not transfer RK-40K24 or RK-40S24 to the white model. If the oven stays on the counter, the open ventilation path is still part of a safe fit.
Compare the exact offer instead of trusting the old ASIN
The frozen source row names R-420LW and historical ASIN B000FGLYYK, but the Amazon detail page did not establish a current exact offer in the saved research. The affiliate destination searches the exact white R-420LW code and carries buyershortlists-20. Check any present result for the W suffix, the RK-40W24 kit if needed, and the actual unit rating label. The review uses Sharp's manual for stable model facts and makes no assertion about price, stock, seller condition, sales volume or customer ratings. This keeps an old listing clue from becoming a present offer claim.
Compare documented alternatives by the requirement that matters
Panasonic NN-SN65KB is a smaller black 1.2-cu.-ft. inverter model with 1,200-W output and sensor settings, but its family manual does not confirm a trim kit for the KB suffix. Sanyo EM-S6588S provides a 1.0-cu.-ft. cavity and smaller 12 3/8-inch turntable with ten power levels. Sharp's distinguishing strengths in this group are the larger 14 1/8-inch tray, white finish and exact RK-40W24 path. Choose among them by measured cookware, counter or cabinet location and the model-specific electrical requirements rather than assuming one is universally superior.
What else to compare
For inverter and 15-setting sensor controls with a separate 20-A circuit, compare Panasonic NN-SN65KB; for a smaller basic-size model with a 12 3/8-inch tray, compare Sanyo EM-S6588S. Sharp's 1.4-cu.-ft. cavity and exact white trim-kit mapping suit a different combination of fit and installation needs.
Before you buy
What capacity and output does Sharp list?
The manual gives 1.4 cu. ft. and 1,100 W microwave output; electrical input is separately listed at 1,600 W.
What size is the turntable?
Sharp lists a 14 1/8-inch diameter in the R-420L/R-425L operation manual.
Does the white model have a built-in kit?
Sharp maps optional white kit RK-40W24 specifically to model R-420LW.
What outlet supply does the manual specify?
It lists single-phase 120 V / 60 Hz AC, with a grounded outlet and separate circuit recommended.
Is R-420LW the black version?
No. The manual maps W to white and K to black; keep the complete suffix when comparing offers.
Where can I check the current price?
Use the Amazon link for current offers. Check the exact model, seller, product condition, delivery, and return terms. This page does not display a live price or confirm stock.
Sources & review basis
We use the following manufacturer documentation for the product features above. Our suitability notes and buying advice are editorial judgments based on those features, not measured performance results.
- Sharp R-420L/R-425L operation manual; suffix and kit mapping for R-420LW ↗ — checked October 10, 2026.
- Sharp R-420L/R-425L operation manual. PDF page 0 maps suffix W to white; page 4 gives counter clearance and kit RK-40W24 for R-420LW; page 22 lists 120 V / 60 Hz, 1,100-W output, 1,600-W / 13.5-A input, 1.4 cu. ft. and 14 1/8-in. turntable. ↗ — checked October 10, 2026.
The decision
Choose R-420LW when its white finish, 1.4-cu.-ft. cavity, 14 1/8-inch turntable and exact RK-40W24 option match your measured space. Preserve the suffix and follow the manual's counter or kit installation instructions.
Is it the right fit?
Check the exact model and today’s offers on Amazon.