Standard Aluminum Shell

Classic American half ball ("HB") button shell is the upholstery standard. Aluminum version has a less severe profile than rust-resistant versions, but a similar wall height. Somewhat softer than RR but impervious to rust —the only shell material appropriate for marine use and other outdoor applications.

Use Low Wall AL shells for sizes #16, #18, and #20 (essentially "standard" in these smallest sizes, but technically different so we list them separately).

Suitable for all button back materials. Fits standard American half ball button dies.