Making a large tarp

Two ShellTas can be zipped together to make a large sheet about 280cm by 260cm. It can then be pegged out like a tarp. However, care must be taken not to put undue tension across the zips and this large expanse of fabric benefits from more than two treking poles as support. That said, a number of years ago on the Haute Route, we used two ShellTAs to accommodate four of us with just one trekking pole and several ice axes. At that time the zips didn’t match (they were prototypes) so we just overlapped them in the middle. We used them twice, the second time at over 3000m.