Does the LMT MARS-LS work with the LMT Barreled Flat Top Upper?
Lewis Machine & Tool lower and Lewis Machine & Tool upper compatibility
Yes, they fit
The LMT MARS-LS works with the LMT Barreled Flat Top Upper. Our compatibility rules found no conflict between them.
No one has built this exact setup yet, but Lewis Machine & Tool lowers with Lewis Machine & Tool uppers are a common pairing.
Counted from real GunPartPicker builds: parts lists people put together while planning to buy.
Checked by the same rules the AR builder runs on every part you add: caliber, frame size, receiver pattern, thread pitch and gas length.
Fit is judged from the specs retailers list, which can be missing or wrong. Confirm with the manufacturer before you buy, and have a qualified gunsmith check any build before you fire it.
How often builders pair the Lewis Machine & Tool lower and Lewis Machine & Tool upper
Backed by tens of thousands of qualified builds that have both a lower and an upper.
Share of builds with the LMT MARS-LS and any upper
LMT MARS-LS
- Of lower picks
- 0.1%
- Median paid
- $817
LMT Barreled Flat Top Upper
Not in enough builds yet to report.
How we count ⌄
These shares come from GunPartPicker's build data: real parts lists people put together while planning a purchase, not sales or surveys. A build counts a part only when it is the final pick for its slot, so parts that were swapped out never count. Fit never comes from these numbers; it comes from our compatibility rules alone.
Frequently built with the Lewis Machine & Tool lower and Lewis Machine & Tool upper
The part builders pick most often in each slot alongside these two, checked against both. Parts that conflict are left out.
Charging Handle

Aero Precision Breach Small Levers
Fits both
Suppressor
Bolt Carrier Group
Stock & Brace
Handguard

Troy Industries Freefloat M-LOK Rail
Fits both
LMT MARS-LS vs LMT Barreled Flat Top Upper: specs and prices
| LMT MARS-LS | LMT Barreled Flat Top Upper | |
|---|---|---|
| Best price | $969.30 at Brownells | $683.99 at KY Gun Company |
| Stores | 2 of 3 in stock | 0 of 2 in stock |
| Assembly | Complete | Complete |
| Platform | AR-15 | AR-15 |
| Caliber | Multi | n/a |
| Trigger Pin | .154 | n/a |
| Finish | Hardcoat Anodized | n/a |
| Receiver Type | n/a | Flat Top |
| Length | n/a | 10.5 |
Both for $1653.29 at today's best prices.
Today's best prices and 90 day price history
Every store we track for each part, cheapest in stock first. Prices are checked through the day.
Price history, last 90 days
- LMT MARS-LS: lowest $816.99 on Jul 5, highest $969.99 on Oct 2 over the last 90 days.
- LMT Barreled Flat Top Upper: lowest $683.99 on Jul 5, highest $706.50 on Jul 6 over the last 90 days.
Upper Receivers frequently paired with the LMT MARS-LS
Most picked next to it in real builds. Only parts our rules say fit the LMT MARS-LS are listed.
Lower Receivers most paired with Lewis Machine & Tool uppers
The LMT Barreled Flat Top Upper is not in enough builds yet, so these are the most picked next to any Lewis Machine & Tool upper. Only parts our rules say fit the LMT Barreled Flat Top Upper are listed.




















