LITTLE KNOWN FACTS ABOUT TYPES OF SCREW HEADS.

Screws have several different drive types, each with its own advantages and drawbacks. The slotted screw will be the oldest sort, with drawings within the 16th century showing screws with slotted heads. A screw push known as a double hex incorporates a socket that is certainly made up of two coaxial offset hex recesses and will be driven with stan

Transfer pipettes that has a bulb in the lower finish, suitable for transferring viscous liquids like serum and blood. determine 1. Comparison from the air-displacement and good-displacement pipettes. Panel A demonstrates the working basic principle of air-displacement pipettes with the piston integrated into the reduced Element of the pipette and