INCLUDES 4 DONUT BUMPERS TO HELP PROTECT DOORWAYS AND WALLS. ATTACHES TO BOTTOM OF POST. SET OF 4 CASTERS. TEMPERATURE RESISTANCE SHORT TERM -40 degreesF TO +248 degreesF (-40 degreesC TO +120 degreesC) CONTINUOUS -4 degreesF TO +176 degreesF (-20 degreesC TO +80 degreesC)