Convoy M21B vs Fenix UC35 V2.0 USB size comparison

By · Updated · How we compare and rank

The Fenix UC35 V2.0 USB is 1.5 mm (0.06 in) shorter than the Convoy M21B, and 10.3 mm narrower at its widest point. Weights are published on different bases (without battery vs listed), so compare them with care.

Convoy M21B · 141.5 mmFenix UC35 V2.0 USB · 140 mm

The Fenix UC35 V2.0 USB is 1.5 mm (0.06 in) shorter than the Convoy M21B, and 10.3 mm narrower at its widest point. Weights are published on different bases (without battery vs listed), so compare them with care.

Dimensions

Convoy M21B
Check price ↗
Fenix UC35 V2.0 USB
Check price ↗
Length141.5 mm (5.57 in)140 mm (5.51 in)−1.5 mm
Head / width35.7 mm (1.41 in)25.4 mm (1.00 in)−10.3 mm
Body27.1 mm (1.07 in)23.5 mm (0.93 in)−3.6 mm
Weight120 g listed89 g without battery
Battery2170018650 / 2x CR123A
Max output—1,000 lm
Throw—266 m
TypeEDCEDC
Price$48.99 at flashlightgo.com, as of Nov 4, 2026$89.95 at fenixlighting.com, as of Nov 4, 2026
Sourceflashlightgo.com sourced
Output depends on LED option
fenixlighting.com sourced

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M21B vs UC35 V2.0 USB: how they differ

Size and weight

The Fenix UC35 V2.0 USB is the shorter light: 140 mm (5.51 in) against 141.5 mm (5.57 in), a difference of 1.5 mm (1%). At its widest point the Fenix UC35 V2.0 USB is 10.3 mm slimmer (25.4 vs 35.7 mm). Weights are published on different bases (Convoy M21B: 120 g listed; Fenix UC35 V2.0 USB: 89 g without battery), so they are not directly comparable.

Brightness and throw

The Fenix UC35 V2.0 USB is rated at 1,000 lm; we have no published maximum for the Convoy M21B. Output for the Convoy M21B depends on the LED option chosen.

Battery

The Convoy M21B runs on a removable 21700 battery; the Fenix UC35 V2.0 USB runs on removable 18650 / 2x CR123A batteries. For scale, a 21700 cell is about 21 × 70 mm and a 18650 about 18 × 65 mm (nominal).

Price

When we checked on Nov 4, 2026, the Convoy M21B was $48.99 at flashlightgo.com and the Fenix UC35 V2.0 USB $89.95 at fenixlighting.com, so the Convoy M21B cost $40.96 less. Prices change often, so check the current price before you buy.

Type

Both are EDC lights in our catalog with a tube body.

Which should you buy?

Choose the Fenix UC35 V2.0 USB if you want a slimmer profile (10.3 mm narrower). On the specs we track, the Fenix UC35 V2.0 USB is ahead or level everywhere; the Convoy M21B makes sense mainly if its price, interface or a feature we don't track suits you better. We compare published size, weight, output, throw and battery only, not runtime, interface or build quality.

Check price ↗ Convoy M21B Check price ↗ Fenix UC35 V2.0 USB

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M21B vs UC35 V2.0 USB FAQ

Which is smaller, the Convoy M21B or the Fenix UC35 V2.0 USB?

The Fenix UC35 V2.0 USB is the shorter light: 140 mm (5.51 in) against 141.5 mm (5.57 in), a difference of 1.5 mm (1%). At its widest point the Fenix UC35 V2.0 USB is 10.3 mm slimmer (25.4 vs 35.7 mm). Weights are published on different bases (Convoy M21B: 120 g listed; Fenix UC35 V2.0 USB: 89 g without battery), so they are not directly comparable.

Which is cheaper, the Convoy M21B or the Fenix UC35 V2.0 USB?

When we checked on Nov 4, 2026, the Convoy M21B was $48.99 at flashlightgo.com and the Fenix UC35 V2.0 USB $89.95 at fenixlighting.com, so the Convoy M21B cost $40.96 less. Prices change often, so check the current price before you buy.

Do the Convoy M21B and Fenix UC35 V2.0 USB use the same battery?

The Convoy M21B runs on a removable 21700 battery; the Fenix UC35 V2.0 USB runs on removable 18650 / 2x CR123A batteries. For scale, a 21700 cell is about 21 × 70 mm and a 18650 about 18 × 65 mm (nominal).

Compare Convoy M21B with similar lights

M21B vs E40RM21B vs PD40R V3.0M21B vs Seeker UltraM21B vs TK16 V2.0M21B vs P20iXM21B vs LD35R

Compare Fenix UC35 V2.0 USB with similar lights

UC35 V2.0 USB vs PD35R ACEUC35 V2.0 USB vs PD36R V2.0UC35 V2.0 USB vs PD35RUC35 V2.0 USB vs MH12 ProUC35 V2.0 USB vs PD35 V3.0UC35 V2.0 USB vs T35

More

Convoy M21B size & specsFenix UC35 V2.0 USB size & specsAll Convoy lightsAll Fenix lightsBest EDC flashlights

Sources

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