This reconditioned and cleaned soda syphon/seltzer bottle was originally marketed in the period between 1934 and 1955 and was made with a high quality hand blown Czech glass body, covered by a braided steel mesh coat for safety.  It has an chromed collar and, unlike the earlier Type C, the CO2 capsule and key do not need to be left in place during use.    This example has the more stable wide, flat, base which possibly makes it more stable on a side-board or club bar.  The chrome plated pewter head has the slightly more common cap-on-a-chain dust cap to prevent the ingress of debris into the CO2 charging socket.   (The replacement top cap on the head is made from highly polished aluminium.). The chrome plating on the head and neck skirt are both in above average condition and the red "max fill level" line is almost complete, which is rare.