YT28 Air leg Rock drill/hand held jack hammer/rock drilling machine/air hammer/ well drilling/mining drilling machine FEATURES OF YT24/YT28 AIR LEG ROCK DRLL /HAND HELD JACK HAMMER/ROCK DRILLING MACHINE/AIR HAMMER/WELL DRILLING/ MINING DRILLING MACHINEFit for wet drilling in medium-hard or hard rock.Grouped control mechanism,quick to start up, with "air on ,water on, air off,water off" mechanism, ...