most efficient space heater

BLACK+DECKER Ceramic Heater, Space Heater for Office Desk, Home Office & Personal Use, 2 Heat & Fan Only Settings, Thermostat

Costway 1500W Portable Electric PTC Heater Swing Space Heater w/ 24H Timer &Thermostat

Sengoku HeatMate Portable Instant Heat Graphite Medium Tower Electric Heater for Small Areas in Homes, Offices, and Workshops, White

Portable Radiator Space Heater, 1500W, 7-Fin, 3 Heat Settings, White

Geneva Industrial Portable Ceramic Heater 3 Setting Electric Shop Space Heater Indoor/Outdoor Hot Air Fan with Adjustable Thermostat, Black

Karl Home 1500-Watt 20.5 in. Electric Wall Mount / Freestanding Ceramic PTC Space Heater

ZAFRO Space Heater, Portable Heater Electric Ceramic Fan Small Heaters Handle Indoor Use,Child Lock,Tip-Over & Overheat Protection

Good Housekeeping Oscillating Ceramic Tower Space Heater with Remote, 30", Black

Lasko 101 MyHeat 200 Watt Small Energy Efficient Portable Electric Ceramic Space Heater w/Cool Touch Exterior for Office Desk & Home, White (3 Pack)

Kismile Electric Space Heater, Portable Heaters for Indoor Use, Engineered for Small Rooms, with Handle, Dual Heating modes 750W/1500W

Lasko 101 MyHeat Small Portable Personal Electric 200 Watt Ceramic Space Heater for Office Desk and Home, White

Brentwood® H-F301BK 1,500-Watt-Max Portable Electric Space Heater and Fan, Black

1500W Ceramic Space Heater Portable Electric Heater for Indoor Use

Sengoku KeroHeat Indoor Outdoor Portable Convection Kerosene Heater 23,500 BTU

VOLTORB Portable Electric Space Heater w/Remote Control & Fan Only Mode, Black

R.W.FLAME Space Heater, Portable Heater Electric Ceramic Fan Small Heaters Handle Indoor Use,Child Lock,Tip-Over & Overheat Protection,ECO Mode

Mr. Heater 11,000 BTU Wind Resisting Buddy FLEX Liquid Propane Portable Radiant Space Heater for Fishing, Camping, and Outdoors with Overheat Safety

Kismile Electric Space Heater, Portable Heaters for Indoor Use, Engineered for Small Rooms or Offices, Dual Heating modes (950W/1500W)

Karl Home 1500-Watt 17 in. Electric Tower Space Heater with 3 Heat Settings

TCL 5100 BTU SACC (8,500 BTU ASHRAE) Smart Portable Air Conditioner Fan & Dehumidifier (H5P44W): AC Unit for 100-300 sq. ft.

Small Space Heater,Portable Space Heater,with Overheat & Tip-Over Protection Office Room Desk Indoor Use (Black)

R.W.FLAME Small Space Heater, 1500W Space Heaters for Indoor Use, Portable Heater with Thermostat, Knob Control, Overheating & Tip-Over Protection

Karl Home 1500-Watt 12.3 in. Electric Wall Mount / Freestanding Ceramic PTC Space Heater with Handle

Handy Heater Instant Heat