The Universal Penetrometer tests a wide variety of materials by penetration of weighted needles or cones. Main applications are for bituminous materials, but waxes, greases, foods, and pharmaceuticals are among other products tested. Penetration is read from a 5in (127mm) diameter indicator dial of 400 divisions, each representing 0.1mm of penetration. Gilson offers heavy-duty units for manual and automatic use and a lighter, portable model for field work or users with a limited work load or budget. All meet ASTM and AASHTO standards when fitted with proper needle or cone.

Manual Penetrometer is ruggedly constructed for accurate, sensitive measurements. The aluminum base has a machined, grooved table with leveling screws and rubber inserts to protect tips of needles and cones. Two stainless steel rods act as support guides for a cast aluminum head with coarse/fine adjustments and a calibrated friction-free plunger mechanism. Indicator dial has instant zero reset. Any needle or cone with standard 1/8in (3mm) diameter stem may be mounted to the 47.5g plunger assembly. A standard 2.5g ASTM D 5 Needle (HMA-180) and two additional loading Weights (50g and 100g) are included. Order needles or cones for other tests separately as needed.

Automatic Penetrometer is the same as the HM-320, but has a button release mechanism with digital timer to automatically stop the plunger when the preset time from 0.1—9.9 seconds expires.

Light Duty Penetrometer has features like the manual model but is smaller and easy to disassemble. One Model Needle and an additional Loading Weight (50g) are provided.