A supplemental safety device not to be used in place of the original equipmentparking brake. When used with existing vehicle parking brake, the Brake Lockuses a portion of the vehicle’s hydraulic service brake system to provideadditional brake holding action. For brake fluid systems – 12 volts DC -includes toggle switch. Approximate Weight: 4 lbs. Replaces part number 02-620-171 End fittings need a 3/16 adapter