What is width of the inside wall unit. The 18,000 BTU unit?

Thank you for your question. The indoor air handling unit included with this 18,000 BTU mini split system has a width of 37.99". It has a depth of 8.46" and a height of 12.56". The outdoor condenser unit has a width of 31.50", a depth of 13.11" and a height of 12.56". For anymore assistance, please give us a call.