... Volume Sanitary Napkins matches one piece of micro-spring balance, used in conjunction with micro-spring balance, It could measure volume bleeding quickly and ... using Total Blood Volume Sanitary Napkins, use zero- figure Micro Spring Balance to hang Total Blood Volume Sanitary Napkins, read the ... Volume Sanitary Napkins, use the same way to read the balance scale and record the weight,Mark B, so, A-B ...