Sea to Summit Alto TR1 vs Six Moon Designs Lunar Solo

Two shelters, measured against each other on the figures that decide whether they work on a bike.

The short answer

The Alto TR1 takes pitching on hard ground; the Lunar Solo takes weight, floor space, headroom and price. On a bike the pole set usually decides it before the rest do.

Assembled from the differences below rather than written over them. Every figure is a published measurement or computed from one — nobody here has used either one.

Where they differ

7 of the 7 things we can measure come out differently.

Poles to carry

the Lunar Solo has no pole set at all, the Alto TR1 does
Sea to Summit Alto TR1
450mm folded
Six Moon Designs Lunar Solo
None — trekking-pole shelter

A trekking-pole shelter has nothing to fit across your bars, which removes the constraint entirely — but you then need poles from somewhere, strapped to the frame or bought separately. It is a different problem, not a smaller one.

Minimum weight

196g lighter on the Lunar Solo
Sea to Summit Alto TR1
936g
Six Moon Designs Lunar Solo
740g

Trail weight where the maker publishes one — fly, inner and poles, without the stuff sacks or the footprint. Worth reading against the pole length rather than instead of it: a Bikepack edition is usually a few grams heavier for shorter poles.

Construction

Alto TR1 is double wall, Lunar Solo is single
Sea to Summit Alto TR1
double wall
Six Moon Designs Lunar Solo
single wall

A double wall puts a gap between you and the condensation; a single wall saves the weight of the second layer and puts the condensation on the inside of your shelter. Which is right depends on where you sleep, not on which is better.

Pitching

Alto TR1 needs less from the ground
Sea to Summit Alto TR1
semi
Six Moon Designs Lunar Solo
Needs stakes

Freestanding matters on a bike trip more than on a hike: gravel bars, wooden platforms and hardpack are where you end up when you are following a road, and none of them take a stake.

Floor area

0.47m² more floor in the Lunar Solo
Sea to Summit Alto TR1
215 × 107cm — 2.29m²
Six Moon Designs Lunar Solo
228 × 121cm — 2.76m²

Inner length by inner width as published. On a bike trip the floor also has to take whatever you brought inside off the bike, so a few centimetres is not nothing.

Peak height

17cm more headroom in the Lunar Solo
Sea to Summit Alto TR1
108cm
Six Moon Designs Lunar Solo
125cm

Whether you can sit up, which decides how a rained-out afternoon goes.

Price

$165 between them
Sea to Summit Alto TR1
$380
Six Moon Designs Lunar Solo
$215

As we hold it. Shelter prices move more than most gear, so check before you commit.

Side by side

Including the rows where they are level.

Sea to Summit Alto TR1Six Moon Designs Lunar Solo
Poles to carry450mm foldedNone — trekking-pole shelter
Minimum weight936g740g
Constructiondouble wallsingle wall
PitchingsemiNeeds stakes
Floor area215 × 107cm — 2.29m²228 × 121cm — 2.76m²
Peak height108cm125cm
Price$380$215
Sea to Summit
Alto TR1
$380 · 1050g
Six Moon Designs
Lunar Solo
$215 · 740g

Other comparisons with these two