HALL EFFECT DEVICE - Classes 257, 438
HALOGEN* - Class 075
HALOGENATED HYDROCARBON - Classes 514, 520
HALOGENS - Classes 257, 423, 588
HAMMER HEAD - Class 173
HAND (MANIPULATE) - Class 269
HAND-ACTUATED(*); HAND-OPERATED(*) - Class 024
HANDLE - Class 081
HANDLE-LEVER (OR GRIP-LEVER) - Class 081
HANDLE-MEMBER - Class 081
HAPTEN - Class 436
HARMFUL CHEMICAL SUBSTANCE - Class 588
HARMONIC OR SINE WAVE OSCILLATOR - Class 331
HAZARDOUS WASTE - Classes 435, 588
HBT - Class 438
HDC - Class 438
HDI - Class 438
HDMI - Class 438
HEAD (Marker) - Class 347
HEAD: - Class 123
HEADEND - Class 725
HEADER - Classes 053, 257
HEARTH - Class 373
HEAT - Class 374
HEAT SINK - Class 257
HEATED CATHODE - Class 313
HEAVY METAL - Classes 260, 424, 532, 588
HEAVY METAL* - Class 075
HEAVY METALS - Class 257
HELICAL COIL SPRING - Class 267
HEMT - Class 438
HERBICIDE - Class 504
HET - Class 438
HETERO - Class 435
HETERO ATOM - Class 008
HETERO RING - Classes 008, 514, 532
HETEROCYCLIC - Classes 260, 424, 430, 510, 520
HETERODYNE FREQUENCY - Class 331
HETEROJUNCTION/HETEROINTERFACE - Class 257
HETEROJUNCTION/HETEROINTERFACE - Class 438
HETEROSTRUCTURE - Class 257
Hi-C - Class 438
HIC - Class 438
HIGH ELECTRON (HOLE) MOBILITY TRANSISTOR (HEMT) - Class 257
HIGH ELECTRON MOBILITY TRANSISTOR (HEMT) - Class 438
HIGHER FATTY ACID - Classes 106, 106, 106, 204, 507, 507, 510
HIGH-VACUUM TUBE - Class 315
HIMOS - Class 438
HINGE AXIS - Class 016
HINGE PIN - Class 016
HINGED MEMBER - Class 016
HIPOX - Class 438
HLB - Class 516
HMDS - Class 438
HNA - Class 438
HOLDER - Class 401
HOLDER MOUNTED FOR MOVEMENT - Class 269
HOLDER SUPPORT, MOUNT, OR BASE - Class 269
HOLDING CURRENT - Class 257
HOLDING ELECTRODES - Class 313
HOLE - Classes 257, 438
HOLE FLOW - Class 257
HOLLOW WORK - Class 072
HOLOGRAPHY - Class 359
HOMOGENEOUS (FISSION) REACTOR - Class 376
HOMOGENEOUS FUEL - Class 376
HOMOGENIZE - Class 065
HOMOJUNCTION - Classes 257, 438
HOMOPOLAR OR UNIFORM-FIELD MOTORS - Class 318
HOPPER - Class 221
HOT CARRIER DIODE - Classes 257, 438
HOT ELECTRONS - Class 257
HOT-TOP - Class 164
HPSC - Class 438
HTO - Class 438
HTSC - Class 438
HULL or HULLING - Class 099
HUSK - Class 460
HYBRID CIRCUIT - Classes 257, 438
HYBRID TYPE NETWORK - Class 333
HYDROCARBON - Class 044
HYDROMETALLURGY - Class 075
HYDROPHILIC - Class 210
HYDROPHOBIC - Class 210
HYDROSOL - Class 516
HYPERFILTRATION - Class 210
HYPERGOLE - Class 060
HYPERLINK - Class 715