a collection tube and method for drawing samples of blood and other biological fluids , such tube having a tip construction effective in promoting the entry of such fluids into the tube and , where the tube is designed to fill by capillary attraction , in enhancing the rate and extent of such action . the fine - bore tube is transparent and is cylindrical in shape with its tip beveled to define an oval planar end surface , the long axis of the oval intersecting a plane normal to the longitudinal axis of the tube at an acute angle within the range of about 35 ° to 60 °.