HB Instrument Company Baum and Specific Gravity Hydrometers. Designed for sampling and filling procedures this instrument is a practical and inexpensive device. The bubbler serves as a release valve for the hydrometer and allows one to break the bulb to get extra fluid out of the system. A separate bulb piercing device is included as well as a separate plug for the test tube holder. The hydrometer is a simple tube with a ball bearing at the end of the stainless steel rod which is pulled from the tube. A marking pin helps to identify the type. The bubbler end is attached to the tube so that the bubbler can be set anywhere in the vessel. A separate plug is included for the half inch models. Bubblers are a must for the lab and plant however they are not very useful for the pilot and cylinder testing as they do not have a ball bearing. Specifications for HB Instrument Company Baum and Specific Gravity Hydrometers 50315 : RangeSpecific Gravity: 0.690 to 0.800 RangeBaum B : 43 to 70 SubdivisionsSpecific Gravity: 0.002 Subdivisions B : 0.5 Unit: Each (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine HB Instrument Company products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Labware & Accessories with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for HB Instrument Company Labware & Accessories. We are an authorized supplier to all federal and state government agencies as well as to research and educational institutions and can facilitate volume orders on many types of laboratory equipment lab consumables and other products to help fulfill your specific needs. We offer Free Shipping and FREE USPS shipping to APO and FPO addresses on all orders in our store over 49. Please refer to our APO/FPO Shipping and Export Restrictions for more information on export to APO/FPO addresses. In addition to the HB Instrument Company Baum and Specific Gravity Hydrometers 50315/ 34670-128 we carry a full complement of Labware & Accessories as well as other product offerings from HB Instrument Company. We also carry a full line of HB Instrument Company accessories to help meet your laboratory and scientific needs. For a complete selection of HB Instrument Company Labware & Accessories please visit our HB Instrument Company page. For more brand name Labware & Accessories please visit our Labware & Accessories store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. HB Instrument Company Baum and Specific Gravity Hydrometers 50315