The 6AL5W is the special quality version of the 6AL5. The improvements relate to resistance to the effects of vibration. The CV Type for this valve is the CV4007 and this is the most prominent set of lettering on the glass. The 6AL5W is near the base and has been over-printed with the CV information.
This premium version is designed to be used in areas of shock and vibration such as aircraft equipment.
The two diodes are completely separate flat structures separated by a flat metal screen.
The electrode are here end on. The W of the original Type designation can be seen on the lower right.
One way of improving vibration resistance is to use double mica sheets top and bottom. Here a single mica disc is used but it seems a little thicker than those used on the commercial versions.
The thin glass tube envelope is 18 mm in diameter, and excluding the B7G base pins is 36 mm tall.