Robinair 17800C Multi-Refrigerant Recover, Recycle, Recharge Machine — $10,549.70Enerpac SC10HTB 10 Ton, Four Hydraulic Cylinders and Hand Pump Toolbox Set — $6,826.67Powerex SLAE05EHP 5 HP High Pressure Oil-Less Scroll Air Compressor Bare Pump, 145 PSI — $6,083.84Milwaukee 2922-22M M18 FORCE LOGIC Press Tool Kit with ONE-KEY, 1/4 in - 7/8 in Streamline ACR Jaws — $4,605.02Husqvarna K1270 Rail 16" Rail Power Cutter — $3,818.08Detex AO19-1 Low Energy Automatic Door Operator for Single Doors, Right Hand Push — $3,745.56Durham Super Duty Bin Cabinet, 48 in W x 24 in D x 78 in H, 84 Blue Bins, 2 Adjustable Shelves, 6 Door Shelves, 12 Gauge Steel, Gray — $2,351.02Pace 8007-0597 MBT360 Multi-Channel Soldering and Rework Station w/ 3 Handpieces, 115V — $2,271.35Billy Goat KV601SP 27" Self-Propelled Outdoor Litter Vacuum, 190cc — $1,906.10Baldor EHM3311T Super-E HVAC Motor, 7.5 HP, 1770 RPM, 213T, OPSB, 230/460V 3-Phase — $1,397.88JB Industries DV-285N Platinum 10 CFM Vacuum Pump, 1/2 HP, 115V — $1,181.45Von Duprin 958003-00 Quiet Electric Latch Retraction Retrofit Kit, 3 ft — $995.63Baldor EM3558T 2 HP 1755 RPM 145T TEFC Motor, 208-230/460V, 3-Phase — $922.87Vestil LAD-7-21-P-EZ Steel Rolling Warehouse Ladder, 7 Step, Perforated, 50 Degree, 21 in Deep Top Step — $908.46Hubbell HBL4100P9W IEC Pin and Sleeve Plug, 3-Pole 4-Wire, 100A, 250V, Watertight, Blue — $872.38Lexmark MS821n Monochrome Laser Printer, 55 ppm — $843.01Barksdale 9021-MC-A Shear-Seal Manual Directional Control Valve, 1/4 in — $787.66Rite-Hite 504AR Holdown-Ramp Control w/5016 Ratchet Bar & Patented Auto Release — $741.85Rubbermaid FG9W7300BLA Mega Brute 120 Gallon Black Executive Series Mobile Waste Collector — $723.24Walter 30A606 Straight-Mate 6" 110V Straight Grinder — $706.57Buckhorn BH4845342010000 48 x 45 x 34 in. Collapsible Bulk Shipping Container, Black, 2500 lb — $694.81Louisville Ladder FE4228HD 28 ft. Fiberglass Extension Ladder, ANSI Type IAA, 375 lbs. Load Capacity — $694.82Alarm Lock Trilogy DL2700IC26D T2 Digital Keypad Lever Lock, SFIC Prep, Satin Chrome (Less Core) — $681.73Yale AU5405LN-626 5400LN Series Grade 1 Storeroom Cylindrical Lever Lock, Augusta Lever, Satin Chrome — $548.80APC RBC55 Replacement Battery Cartridge #55 — $495.83Yellow Jacket 46013 BRUTE II 4-Valve Test and Charging Manifold with 60 in Hoses — $481.83Odyssey ODX-AGM24M Extreme Series 12V Group 24 Marine Dual Purpose AGM Battery, 840 CCA — $465.49Amano BX-1500 Electronic Time Recorder — $440.99DEWALT DCN930B 20V MAX XR Brushless 30-Degree Paper Tape Framing Nailer (Bare Tool) — $391.02FLIR TG165-X MSX Thermal Imaging Camera, 80 x 60, -25°C to 300°C, with Bullseye Laser — $391.02Fellowes Powershred 99Ci 18-Sheet Cross-Cut Paper Shredder, P-4, 100% Jam Proof — $382.19Bard S8105-039 CW Condenser Fan Motor, 1/3 HP, 208-230V, 825 RPM — $341.81Dayton 3YU59 1/2 HP Submersible Sump Pump, 1-1/4 in MNPT, 120V AC, Vertical Float — $297.86Berko SRA Series SRA2027DS Commercial Fan-Forced Small Wall Heater, 2000/1000W 277/240V — $294.12ESAB Dual Shield 710X Gas-Shielded Flux-Cored Welding Wire, .045 in x 33 lb Spool — $279.30Bendix K021557 SR-7 Spring Brake Modulating Valve — $278.50Dayco 80062 Fuel Line Hose, 5/16" ID x 250 ft — $266.30GRK R4 Multi-Purpose Framing Screw #9 x 3-1/8 in. (00105) — $265.57Maxx Ice 1858904400 Water Pump for MIM250/450 Ice Machines — $262.17OTC 7947 8-Way Slide Hammer Puller Set with Storage Case — $261.66DEWALT DCE560B 20V MAX Cordless Adhesive Gun, 10 oz / 300 ml (Tool Only) — $259.70WEG .7536OS3EJPR56C-S Jet Pump Motor, 0.75 HP, 3600 RPM, 56C Frame, ODP, 3-Phase, 208-230/460V — $249.27Ingersoll Rand 1099XPA 1/2 in Air Ratchet Wrench, 76 ft-lb, 220 RPM — $248.82BN Products-USA BNR6500 1800W Hand-Held Power Mixer, 120V, 2-Speed — $243.04NEXIQ Technologies MPS493033 3-Pin Deutsch 2-Pin Cummins Adapter — $226.86XR 20V MAX Brushless Cordless 3 in. Cut-Off Tool Kit — $223.06Square D 8910DPA53V06 Definite Purpose Contactor, 3 Pole, 50A, 480VAC Coil — $219.41RIDGID 18383 S36 Bolt Cutter Head Assembly, Center Cut — $195.953M Protecta Rebel 3100513 11 ft Web Self-Retracting Lifeline (SRL) with Steel Snap Hook and Anchorage Carabiner — $193.05Honeywell BZE6-2RN18 MICRO SWITCH Medium-Duty Enclosed Limit Switch, Wobble Coil Spring, SPDT, 15A, IP66 — $192.13Bergen Industries GL100182LED 100 ft LED Temporary Construction String Light, 18/2 AWG, 15A, 16,000 Lumens, Yellow — $181.29Norton 8301-689 Architectural Door Closer, Aluminum (689), Sizes 1-6, Tri-Style — $173.81AC Works L1530PR-025 SOOW 10/4 NEMA L15-30 30A 3-Phase 250V Industrial Rubber Extension Cord, 25 ft — $165.61UEI DM525 True RMS Wireless Digital Multimeter, 1000V AC/DC — $159.233M 7000126728 Adflo Leather Belt 15-0099-16, 1 EA/Case — $155.84Honeywell L6006C1018 Aquastat Controller - High or Low Limit / Circulator Control, Strap-On, 65-200 F — $153.38LOCTITE 271 Red Threadlocker, 250 ml Bottle — $147.14DeWalt DW099S Tool Connect 100 ft. Laser Distance Measurer — $143.6216 Pc. 72-Tooth 12 Point Ratcheting Combination Metric Wrench Set — $141.70CyberPower EC850LCD Ecologic UPS System, 850VA/510W, 12 Outlets, LCD — $129.31Blue Demon ER308L-023-10 Stainless Steel MIG Welding Wire, .023 in, 10 lb Spool — $127.88Buyers Products RM62000 6-Ton Receiver Mount Combination Hitch with 2 in Ball — $126.41ABB AF09ZB-30-10-21 Railway Contactor, 3-Pole, 1NO Auxiliary, Coil 24-60V AC / 20-60V DC, Screw Terminals — $112.03Milwaukee 48-73-1313 BOLT Orange Safety Helmet, Type 2, Class E — $107.77Honda 06424-ZS9-000AH EU3000is Generator 4-Wheel Kit with Locking Front Swivel Casters — $103.58Genuine Mopar Serpentine Belt for 2003-2012 Dodge Ram Cummins 5.9L/6.7L (Mopar 53041138AE) — $88.18Parker E-Z Mate EZ-501-8FP Pneumatic Push-to-Connect Coupler, 1/2 in Female NPT — $70.66Robinair 17800C Multi-Refrigerant Recover, Recycle, Recharge Machine — $10,549.70Enerpac SC10HTB 10 Ton, Four Hydraulic Cylinders and Hand Pump Toolbox Set — $6,826.67Powerex SLAE05EHP 5 HP High Pressure Oil-Less Scroll Air Compressor Bare Pump, 145 PSI — $6,083.84Milwaukee 2922-22M M18 FORCE LOGIC Press Tool Kit with ONE-KEY, 1/4 in - 7/8 in Streamline ACR Jaws — $4,605.02Husqvarna K1270 Rail 16" Rail Power Cutter — $3,818.08Detex AO19-1 Low Energy Automatic Door Operator for Single Doors, Right Hand Push — $3,745.56Durham Super Duty Bin Cabinet, 48 in W x 24 in D x 78 in H, 84 Blue Bins, 2 Adjustable Shelves, 6 Door Shelves, 12 Gauge Steel, Gray — $2,351.02Pace 8007-0597 MBT360 Multi-Channel Soldering and Rework Station w/ 3 Handpieces, 115V — $2,271.35Billy Goat KV601SP 27" Self-Propelled Outdoor Litter Vacuum, 190cc — $1,906.10Baldor EHM3311T Super-E HVAC Motor, 7.5 HP, 1770 RPM, 213T, OPSB, 230/460V 3-Phase — $1,397.88JB Industries DV-285N Platinum 10 CFM Vacuum Pump, 1/2 HP, 115V — $1,181.45Von Duprin 958003-00 Quiet Electric Latch Retraction Retrofit Kit, 3 ft — $995.63Baldor EM3558T 2 HP 1755 RPM 145T TEFC Motor, 208-230/460V, 3-Phase — $922.87Vestil LAD-7-21-P-EZ Steel Rolling Warehouse Ladder, 7 Step, Perforated, 50 Degree, 21 in Deep Top Step — $908.46Hubbell HBL4100P9W IEC Pin and Sleeve Plug, 3-Pole 4-Wire, 100A, 250V, Watertight, Blue — $872.38Lexmark MS821n Monochrome Laser Printer, 55 ppm — $843.01Barksdale 9021-MC-A Shear-Seal Manual Directional Control Valve, 1/4 in — $787.66Rite-Hite 504AR Holdown-Ramp Control w/5016 Ratchet Bar & Patented Auto Release — $741.85Rubbermaid FG9W7300BLA Mega Brute 120 Gallon Black Executive Series Mobile Waste Collector — $723.24Walter 30A606 Straight-Mate 6" 110V Straight Grinder — $706.57Buckhorn BH4845342010000 48 x 45 x 34 in. Collapsible Bulk Shipping Container, Black, 2500 lb — $694.81Louisville Ladder FE4228HD 28 ft. Fiberglass Extension Ladder, ANSI Type IAA, 375 lbs. Load Capacity — $694.82Alarm Lock Trilogy DL2700IC26D T2 Digital Keypad Lever Lock, SFIC Prep, Satin Chrome (Less Core) — $681.73Yale AU5405LN-626 5400LN Series Grade 1 Storeroom Cylindrical Lever Lock, Augusta Lever, Satin Chrome — $548.80APC RBC55 Replacement Battery Cartridge #55 — $495.83Yellow Jacket 46013 BRUTE II 4-Valve Test and Charging Manifold with 60 in Hoses — $481.83Odyssey ODX-AGM24M Extreme Series 12V Group 24 Marine Dual Purpose AGM Battery, 840 CCA — $465.49Amano BX-1500 Electronic Time Recorder — $440.99DEWALT DCN930B 20V MAX XR Brushless 30-Degree Paper Tape Framing Nailer (Bare Tool) — $391.02FLIR TG165-X MSX Thermal Imaging Camera, 80 x 60, -25°C to 300°C, with Bullseye Laser — $391.02Fellowes Powershred 99Ci 18-Sheet Cross-Cut Paper Shredder, P-4, 100% Jam Proof — $382.19Bard S8105-039 CW Condenser Fan Motor, 1/3 HP, 208-230V, 825 RPM — $341.81Dayton 3YU59 1/2 HP Submersible Sump Pump, 1-1/4 in MNPT, 120V AC, Vertical Float — $297.86Berko SRA Series SRA2027DS Commercial Fan-Forced Small Wall Heater, 2000/1000W 277/240V — $294.12ESAB Dual Shield 710X Gas-Shielded Flux-Cored Welding Wire, .045 in x 33 lb Spool — $279.30Bendix K021557 SR-7 Spring Brake Modulating Valve — $278.50Dayco 80062 Fuel Line Hose, 5/16" ID x 250 ft — $266.30GRK R4 Multi-Purpose Framing Screw #9 x 3-1/8 in. (00105) — $265.57Maxx Ice 1858904400 Water Pump for MIM250/450 Ice Machines — $262.17OTC 7947 8-Way Slide Hammer Puller Set with Storage Case — $261.66DEWALT DCE560B 20V MAX Cordless Adhesive Gun, 10 oz / 300 ml (Tool Only) — $259.70WEG .7536OS3EJPR56C-S Jet Pump Motor, 0.75 HP, 3600 RPM, 56C Frame, ODP, 3-Phase, 208-230/460V — $249.27Ingersoll Rand 1099XPA 1/2 in Air Ratchet Wrench, 76 ft-lb, 220 RPM — $248.82BN Products-USA BNR6500 1800W Hand-Held Power Mixer, 120V, 2-Speed — $243.04NEXIQ Technologies MPS493033 3-Pin Deutsch 2-Pin Cummins Adapter — $226.86XR 20V MAX Brushless Cordless 3 in. Cut-Off Tool Kit — $223.06Square D 8910DPA53V06 Definite Purpose Contactor, 3 Pole, 50A, 480VAC Coil — $219.41RIDGID 18383 S36 Bolt Cutter Head Assembly, Center Cut — $195.953M Protecta Rebel 3100513 11 ft Web Self-Retracting Lifeline (SRL) with Steel Snap Hook and Anchorage Carabiner — $193.05Honeywell BZE6-2RN18 MICRO SWITCH Medium-Duty Enclosed Limit Switch, Wobble Coil Spring, SPDT, 15A, IP66 — $192.13Bergen Industries GL100182LED 100 ft LED Temporary Construction String Light, 18/2 AWG, 15A, 16,000 Lumens, Yellow — $181.29Norton 8301-689 Architectural Door Closer, Aluminum (689), Sizes 1-6, Tri-Style — $173.81AC Works L1530PR-025 SOOW 10/4 NEMA L15-30 30A 3-Phase 250V Industrial Rubber Extension Cord, 25 ft — $165.61UEI DM525 True RMS Wireless Digital Multimeter, 1000V AC/DC — $159.233M 7000126728 Adflo Leather Belt 15-0099-16, 1 EA/Case — $155.84Honeywell L6006C1018 Aquastat Controller - High or Low Limit / Circulator Control, Strap-On, 65-200 F — $153.38LOCTITE 271 Red Threadlocker, 250 ml Bottle — $147.14DeWalt DW099S Tool Connect 100 ft. Laser Distance Measurer — $143.6216 Pc. 72-Tooth 12 Point Ratcheting Combination Metric Wrench Set — $141.70CyberPower EC850LCD Ecologic UPS System, 850VA/510W, 12 Outlets, LCD — $129.31Blue Demon ER308L-023-10 Stainless Steel MIG Welding Wire, .023 in, 10 lb Spool — $127.88Buyers Products RM62000 6-Ton Receiver Mount Combination Hitch with 2 in Ball — $126.41ABB AF09ZB-30-10-21 Railway Contactor, 3-Pole, 1NO Auxiliary, Coil 24-60V AC / 20-60V DC, Screw Terminals — $112.03Milwaukee 48-73-1313 BOLT Orange Safety Helmet, Type 2, Class E — $107.77Honda 06424-ZS9-000AH EU3000is Generator 4-Wheel Kit with Locking Front Swivel Casters — $103.58Genuine Mopar Serpentine Belt for 2003-2012 Dodge Ram Cummins 5.9L/6.7L (Mopar 53041138AE) — $88.18Parker E-Z Mate EZ-501-8FP Pneumatic Push-to-Connect Coupler, 1/2 in Female NPT — $70.66
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Master Lock

Master Lock 491B Grip Tight Circuit Breaker Lockout, Tall and Wide Toggles

Mfr #: 491BBB #: master-lock-491b-master-lock-491b-grip-tight-circuit-breaker-lockoutUPC: 071649229718
Last verified Oct 2, 2026 — price check expired
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✓Returns: Standard returns
⇄ Vendor prices
VendorPriceShipping
Zoro$10.79See site
Hanes Supply$13.86See site
Prices observed across vendors — click a vendor’s name to verify the price on their own page before ordering.

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🗎 Product description from the manufacturer spec sheet

The Master Lock 491B Grip Tight Circuit Breaker Lockout Device fits wide or tall breaker toggles typically found on hi-voltage/hi-amperage breakers. Its patented Grip Tight design locks out circuit breakers with a simple thumb turn and clamping handle for a tight grip on the toggle. It accepts all American Lock and Master Lock safety padlocks and most lockout hasps, and its powder coated steel and reinforced polymer construction stands up in harsh environments.

▦ Specifications spec-checked before it ships

Lockout

Lockout Type
Clamp-On
Lockout Material
Powder Coated Steel/Reinforced Polymer

For

For Circuit Breaker Type
Single Pole
For Voltage
120/277V AC
For Maximum Padlock Shackle Diameter
9/32 in

Overall

Overall Width
1.25 in
Overall Length
3.5 in
Overall Height
1.25 in

More specifications

Item
Single Pole Breaker Lockout
Circuit Breaker Voltage
120/277
Maximum Number of Padlocks
1
Material
Steel
Color
Red
Standards
OSHA 1910.147
Country of Origin
China
⌗ Cross-references every known SKU, MFR & MPN
MPN491B
UPC071649229718
SKUZoro # G1703204
SKUHanes Supply # CON20556