Youth GP Helmet Mono Black,トロイリーデザインアパレル各種入荷しました! – MTBプロショップ BACKYARD GARAGE HOUSE,Troy Lee Designs updated their cover photo. - Troy Lee Designs,D4. Redefining everything & always Evolving. Built with an aerospace shell design and materials, we were able to get the D4 Composite helmet to 1050 grams without sacrificing any strength. The Mips®,Youth GP Helmet Mono Black,