The Alpinum Half Zip Fleece and the Bluebird Shearling Fleece are both pullovers, so what are the differences between them?

The ostrya Alpinum is a lightweight pullover fleece that reduces weight burden^[1], and the Bluebird is a half-zip pullover fleece made with shearling fabric^[2]. Although their outward appearance is similar as pullovers where the neck zipper comes down halfway, their purposes are clearly distinguished by the detailed functions they feature.

The Alpinum incorporates a 4-Way stretch function that stretches in four directions^[3]. Because the fabric flexibly stretches in all directions to match body movements and recovers to its original shape, the garment does not pull and remains comfortable even when you reach your arms out wide or move your upper body.

On the other hand, the Bluebird places a mesh lining on the inside of the collar that wraps around the neck^[4]. Raised-pile thermal fabrics tend to trap heat and sweat around the neck, but backing the inside that touches the skin with a breathable mesh structure helps prevent it from feeling stuffy and sticking even when sweat is absorbed.