Jamieson, Fausset and Brown on 2 Chronicles 4:1

CHAPTER 4

2Ch 4:1. Altar of Brass.

1. he made an altar of brass--Steps must have been necessary for ascending so elevated an altar, but the use of these could be no longer forbidden (Ex 20:26) after the introduction of an official costume for the priests (Ex 28:42). It measured thirty-five feet by thirty-five, and in height seventeen and a half feet. The thickness of the metal used for this altar is nowhere given; but supposing it to have been three inches, the whole weight of the metal would not be under two hundred tons [Napier].

2Ch 4:2-5. Molten Sea.