Used to hook up a QCC1 screw-on LP tank hose and regulator to a Genesis® Silver A or B grill, or for older Spirit® 500, 700 etc. grills.The older Weber® Genesis® 2 and 3 burner gas grills used a quick-disconnect hose and regulator to attach the grill to the LP tank. The newer ones all use the screw-on connector to the LP tank. (In our area, the LP tank exchange company no longer provides quick-disconnect tanks.)One end of this piece is a 1/8 MIP (male iron pipe) fitting which you attach with gas pipe thread tape to your grill. The other end attaches to the hose end of a Weber® #7501 (14 inch) hose and regulator kit or #7502 (21 inch) hose and regulator. (See related items.)(The photo shows a different part. The 434113 adapter is similar, but the large pipe threads on the left are actually about half the size of the flared part on the right.)This is a brass piece, so it won't rust.