The Cane Creek 110 Series Tapered ZS44 ZS56/40 Headset has zero stack (ZS) top and bottom cups that place the bearings inside the confines of the head tube. The advantage of having a headset like this in your frame is that it helps to keep the total stack height (headtube included) to a reasonable measurement. This is especially beneficial on bikes with long travel forks. The framebuilders also benefit by potentially having more room to create the critical junction of the head/down/top tubes.
The 110-Series Headset begins life when they machine the cups from custom drawn, US made seamless 7075 aluminum tube. Each part has been relieved of excess material, inside and out, to keep the weight to a bare minimum while retaining the strength you'll depend on. These cups house the stainless steel sealed cartridge bearings, both of which use Cane Creek's proprietary split-lip seals to keep the grease in and contaminants out.
At the same time, these seals run smoothly against the races with a minimum of drag so your steering feel will be rock solid, yet will respond to the lightest touch on the bars. It's quite possible that dirt and muck will never even reach the bearing seals anyway. The 110 Headset includes low-friction seals on the top bearing cover and on the crown race that effectively seal the cup and bearing contained within.
Another advantageous detail of the 110 is the captured compression ring under the top bearing cover. It facilitates easy assembly and eliminates the possibility of rocking or creaking regardless of the small variations often found in steerer tube diameters. And for lightweight carbon fiber steerer tubes, the extra surface area over other systems ensures a damage-free compressive junction. All these technical details aside, you may simply lust for the jewel-like quality of the 110-Series Headset due to its highly polished finish or its rich anodized colors. And that's perfectly fine too.
The Cane Creek 110-Series ZeroStack Tapered Headset is designed to mate a fork with a 1-1/8" - 1.5" tapered steerer to a tapered head tube having a 44mm I.D. on top and a 56mm I.D. on bottom. It's available in Black only.