Grosvenor Olive Flat Cap

Smart and understated, this flat cap looks and feels effortlessly cool.

This flat cap is perfect for the spring and summer seasons. This chic but understated cap has been re-imagined as a contemporary flat cap style in a smart olive green made from a blend of mohair and linen to keep you cool in the warmer months. 

Grosvenor Olive Flat Cap


  • Peak Length: 6.5 cm
  • Peak Width: 17 cm

Steam from a household kettle and a hard bristle hat brush will help banish any dust and dirt. Brush the hat using short strokes.


The Grosvenor Olive Flat Cap is crafted from 54% mohair and 46% linen from the UK and Ireland. It has a full, 100% cotton lining and is finished in the EU.

Styling & Fitting

The traditional flat cap silhouette is updated with a modern twist for a more flattering fit. This supremely dapper cap suits all styles and face shapes. We recommend you choose one size up.

How to measure your hat size. Read More

Hat Size Chart

Men's Hat Styling

Every Lock & Co. hat purchased is carefully and expertly hand-prepared in our London shop by one of our Hatters, before being whisked out of our famous green front door.

To find your perfect hat size, we suggest booking a virtual appointment for a consultation with one of our hatters here.


At Lock & Co., we sell the finest hats and caps. To achieve this, we pay particular attention to specific hat characteristics - style, fit, durability, and materials. We share these characteristics with you for each hat to help you decide on the perfect choice.

Find Your Size and Style

Flat Cap
At Lock & Co. we offer a wide selection of styles of hats. What defines a hat style is its form: overall shape, height/shape of the crown, width of the brim, and material type. These define a style e.g., Fedora, Trilby, Panama, Cloche, Tweed cap etc.
54% Mohair, 46% Linen
Lock & Co. hats are made of the finest quality material. These can range from exclusive Escorial wool, Scottish Tweed, and cashmere to Toquilla straw for our Panama hat.
Narrow Shape
Different styles of hats have different shapes to them, including classic, fuller, narrow, and standard fits, or with an oversized or a wide brim or sporting a particular shape - bell, birdcage, etc.