Steerer: 1 inch (cut to 180cm from bottom of crown race). Headset: Chris King Ahead set 1 inch.The item "Colnago Master Carbon B-Stay Frame with Star Carbon Forks 50cm" is in sale since Thursday, April 26, 2018. This item is in the category "Sporting Goods\Cycling\Vintage Cycling\Vintage Bicycles". The seller is "big5iron" and is located in Seattle, Washington. This item can be shipped worldwide.