Rab Microlight Alpine Down Jacket vs Sea to Summit Ultra-Sil Nano Daypack 20L (2026)

✍️ By the 247Verdict Editorial Team📅 Updated 05 October 2026

Which is better? We compared both on score, owner ratings, pros and cons.

Rab Microlight Alpine Down Jacket

9.2/10 Excellent

4.7★ (4,800 owners)

700FP hydrophobic down, DWR, lightweight 330g, pack small, Pertex. Rab's packable down jacket.

Full Review

Sea to Summit Ultra-Sil Nano Daypack 20L

8.9/10 Great

4.5★ (3,600 owners)

68g packable, 20L, silnylon, rolls into pocket, 60kg load tested. The emergency daypack.

Full Review

At a Glance

	Rab Microlight Alpine Down Jacket	Sea to Summit Ultra-Sil Nano Daypack 20L
247Verdict Score	9.2/10	8.9/10
Owner Rating	4.7★ (4,800)	4.5★ (3,600)
Verdict	Excellent	Great
Weight	330g	68g

Quick Verdict

Both are strong choices, but the Rab Microlight Alpine Down Jacket edges ahead with a 9.2/10 vs 8.9/10. 700FP hydrophobic down, DWR, lightweight 330g, pack small, Pertex. Rab's packable down jacket. That said, the Sea to Summit Ultra-Sil Nano Daypack 20L is worth considering if 68g packable, 20L, silnylon, rolls into pocket, 60kg load tested. The emergency daypack. Check the current price on Amazon →

Pros & Cons Side by Side

Rab Microlight Alpine Down Jacket

700FP Hydrophobic Down treated to repel moisture — performs in damp UK mountain conditions
Pertex Quantum shell is lightweight while preventing down from escaping
330g packs into its own pocket — the weight and volume of a water bottle
Full front zip, helmet-compatible hood and cuffs seal out cold effectively
Rab's Peak District heritage — the Sheffield brand built for UK mountain conditions specifically

Down insulation performs less well when fully saturated — synthetic alternatives better in extreme wet

Sea to Summit Ultra-Sil Nano Daypack 20L

68g — the weight of a small apple in a pack that carries 20L of gear
Rolls into its own front pocket to the size of an orange — fits in any jacket pocket
Silnylon construction has 60kg load-tested strength despite the negligible weight
Doubles as summit pack, shopping bag and travel overflow — permanent carry 'just in case'
Sea to Summit's outdoor gear engineering heritage in their lightest packable pack

Hip belt absent — all load carried on shoulders limits comfortable carry to 5-6kg maximum
Silnylon squeaks when compressed in a main bag — audible in quiet environments
Single main compartment with minimal organisation — not practical for technical gear access

FAQ

Which is better, Rab Microlight Alpine or Sea to Summit Ultra-Sil 20L?

Is the Rab Microlight Alpine worth the extra cost?

Yes — Rab Microlight Alpine Down Jacket scores higher at 9.2/10 vs 8.9/10.

Who is the Rab Microlight Alpine best suited to?

700FP hydrophobic down, DWR, lightweight 330g, pack small, Pertex. Rab's packable down jacket.

Who is the Sea to Summit Ultra-Sil 20L best suited to?

68g packable, 20L, silnylon, rolls into pocket, 60kg load tested. The emergency daypack.

What are the main downsides of each?

Rab Microlight Alpine Down Jacket: Down insulation performs less well when fully saturated — synthetic alternatives better in extreme wet. Sea to Summit Ultra-Sil Nano Daypack 20L: Hip belt absent — all load carried on shoulders limits comfortable carry to 5-6kg maximum; Silnylon squeaks when compressed in a main bag — audible in quiet environments.

Do owner ratings agree with our verdict?

Largely, yes — Rab Microlight Alpine Down Jacket sits at 4.7★ from 4,800 verified Amazon owners, and Sea to Summit Ultra-Sil Nano Daypack 20L at 4.5★ from 3,600.

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