Emisar D4K vs Streamlight ProTac 2L-X USB size comparison
The Streamlight ProTac 2L-X USB is 27.6 mm (1.08 in) longer than the Emisar D4K, and 1.1 mm narrower at its widest point. Weights are published on different bases (with battery vs without battery), so compare them with care.
The Streamlight ProTac 2L-X USB is 27.6 mm (1.08 in) longer than the Emisar D4K, and 1.1 mm narrower at its widest point. Weights are published on different bases (with battery vs without battery), so compare them with care.
Dimensions
| Emisar D4K Check price ↗ | Streamlight ProTac 2L-X USB Check price ↗ | |
| Length | 103 mm (4.06 in) | 130.6 mm (5.14 in)+27.6 mm |
| Head / width | 28 mm (1.10 in) | 26.9 mm (1.06 in)−1.1 mm |
| Body | 26.5 mm (1.04 in) | 23.9 mm (0.94 in)−2.6 mm |
| Weight | 58 g without battery | 125 g with battery |
| Battery | 21700 | 18650 / 2x CR123A |
| Max output | — | 500 lm |
| Throw | — | — |
| Type | EDC | EDC |
| Price | $39.69 at intl-outdoor.com, as of Nov 4, 2026 | $83.05 at batteryjunction.com, as of Nov 4, 2026 |
| Source | intl-outdoor.com sourced Output depends on LED option | batteryjunction.com sourced |
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D4K vs ProTac 2L-X USB: how they differ
Size and weight
The Emisar D4K is the shorter light: 103 mm (4.06 in) against 130.6 mm (5.14 in), a difference of 27.6 mm (21%). At its widest point the Streamlight ProTac 2L-X USB is 1.1 mm slimmer (26.9 vs 28 mm). Weights are published on different bases (Emisar D4K: 58 g without battery; Streamlight ProTac 2L-X USB: 125 g with battery), so they are not directly comparable.
Brightness and throw
The Streamlight ProTac 2L-X USB is rated at 500 lm; we have no published maximum for the Emisar D4K. Output for the Emisar D4K depends on the LED option chosen.
Battery
The Emisar D4K runs on a removable 21700 battery; the Streamlight ProTac 2L-X 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 Emisar D4K was $39.69 at intl-outdoor.com and the Streamlight ProTac 2L-X USB $83.05 at batteryjunction.com, so the Emisar D4K cost $43.36 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 Emisar D4K if you want a shorter light (27.6 mm shorter). On the specs we track, the Emisar D4K is ahead or level everywhere; the Streamlight ProTac 2L-X USB 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 ↗ Emisar D4K Check price ↗ Streamlight ProTac 2L-X USB
We may earn a commission from these links, at no cost to you. Rankings are never paid for. Disclosure
D4K vs ProTac 2L-X USB FAQ
Which is smaller, the Emisar D4K or the Streamlight ProTac 2L-X USB?
The Emisar D4K is the shorter light: 103 mm (4.06 in) against 130.6 mm (5.14 in), a difference of 27.6 mm (21%). At its widest point the Streamlight ProTac 2L-X USB is 1.1 mm slimmer (26.9 vs 28 mm). Weights are published on different bases (Emisar D4K: 58 g without battery; Streamlight ProTac 2L-X USB: 125 g with battery), so they are not directly comparable.
Which is cheaper, the Emisar D4K or the Streamlight ProTac 2L-X USB?
When we checked on Nov 4, 2026, the Emisar D4K was $39.69 at intl-outdoor.com and the Streamlight ProTac 2L-X USB $83.05 at batteryjunction.com, so the Emisar D4K cost $43.36 less. Prices change often, so check the current price before you buy.
Do the Emisar D4K and Streamlight ProTac 2L-X USB use the same battery?
The Emisar D4K runs on a removable 21700 battery; the Streamlight ProTac 2L-X 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 Emisar D4K with similar lights
Compare Streamlight ProTac 2L-X USB with similar lights
More
Sources
- Emisar D4K: specs from Emisar product page (manufacturer). Price $39.69 from intl-outdoor.com, checked Nov 4, 2026; prices change often.
- Streamlight ProTac 2L-X USB: specs from manufacturer published specs as listed by batteryjunction.com. Price $83.05 from batteryjunction.com, checked Nov 4, 2026; prices change often.
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