This Inline Aluminum Bulkhead Fitting has #6 and #10 A/C fitting for going through firewall. Male O-Ring Style. Bulkhead fittings are an alternative to rubber grommets where A/C and Heater lines pass through the firewall or radiator support. Bulkheads do not include the A/C or Heater Hose fittings.  Dimensions: 2-3/4" wide x 1-1/2" tall Made in the ...