There are times, when walking, that the wind picks up but the weather is too warm to wear either a softshell or hardshell jacket. The question is, what do you do? Well over the last couple of years there has been an increased interest in lightweight windshirts. Various companies have their own variation on this idea but I opted for the Rab Cirrus pull-on.
When they say lightweight they are not kidding. Rab claim 75 grammes (I presume for the medium but could be wrong) for this top and I can believe it. It packs down into a tiny stuff sack less than the volume of a half litre drinks bottle. It can be squashed down further but there isn't much point as it is already very small in size. I have a dislike for the saying "it weighs nothing and takes up no room". What I will say is it takes up so little room and is so light that it is barely noticeable.
The Rab Cirrus is made from Pertex Quantum, the lightest material Pertex make. It feels quite soft but does rustle a little. Pertex say that the material, although very light, is quite strong with good tear and seam strength. However, they do mention that abrasion resistance is not as good as heavier materials. This is where the material could come a cropper.
The Cirrus is light on features, necessary to keep the weight down. From bottom to top, we have single pull hem draw cord to cinch the bottom of the Cirrus in to keep warm air in. The fit of the Cirrus is quite loose allowing for layers to be worn underneath. There is a chest zip which goes around halfway down the top allowing for a good level of cooling when needed. There is a toggle at the back of the collar to allow you ti cinch up the neck and keep the warmth in. Final there are elastic wrist cuffs which have a nice level of elastication. The stay snug to your wrists but don't feel like they are strangling you.
So whats the top like in use. Firstly, I tend to get very hot when walking and generally don't wear many layers so had my concerns about the top. I finally had a reason to wear the top during a walk in the Peak District recently. The air temperature for March was quite high, around 10 degrees centigrade but there was in increasing wind blowing. At this point I was wearing a Rab Aeon long sleeved top and a Keela Summit top. I put the Cirrus on and on I went. At this point I was part weigh up a steep 250 meter approach, the period of the walk where I was liable to generate the most body heat. I had my doubts about the top but found, to my surprise, that although I was perspiring I was not feeling particularly wet. There was a little damp, but nothing I would worry about. For the remainder of the walk, with increasing wind speed and a constant high work rate through boggy and hilly terrain I continued to feel dry. On returning to my car and removing the top I found that the inside of the Cirrus was very slightly damp. I was pleasantly surprised when I found that my layers underneath were dry. Even my back where I had worn my rucksack was dry.
Would I recommend the top? Yes without a doubt, but remember that there won't be many occasions where the top will be needed in the winter if at higher altitudes. This is definitely a top for slightly warmer temperatures lower down such as here in the UK and I have yet to put it to the test in the summer. It would be interesting to hear from anyone who has used the shirt higher up, say the Alps as I can only report on my findings and extrapolate from those.