The tubes are specially used for determination of the erythrocyte sedimentation rate (ESR) by the Westergren’s Method. The mixing ratio is 1 part citrate solution to 4 parts blood. ESR measurements refer to the Westergren method. oduct DescriptionRemark 　　Golor Gode: Black 　　Specifications: Ø13x75mm 　　General Sampling Dosage: 1.6ml, 2.4ml 　　Type of Additive: 3.8% sodium citrate 　　Maximum Vacuum Tolerance: ≤5% 　　Attentions: During the operation, do pay attentions to the followings: 　　1. As soon as the sampling, upside down the tube by 180°shaking and fixing fully. 　　2. Sampling the blood dosage as required to ensuring the test accuracy.