ISO metric thread

acme thread

square thread

buttress thread

60°

55°

47°

29°

provide cushioning effect

provide bearing area

absorb shocks and vibrations

provide smooth surface in place of rough surface

similar to small size tap bolts except that a greater variety of shapes of heads are available

slotted for a screw driver and generally used with a nut

used to prevent relative motion between parts

provided with detachable caps

self locking bolt

same as stud

provided with hexagonal depression in head

used in high speed components