The men’s Pro 65/35 long sleeve polo from Regatta Professional is the ideal baselayer, made from cotton and polyester for comfort that lasts, and finished in a classic polo design.
You might also want to check out these products.

4-Tex stretch waterproof shell jacket
£69.00 + VAT
(£82.80 inc VAT)
Ablaze 3-layer printable softshell
£26.93 + VAT
(£32.32 inc VAT)
Ablaze printable softshell bodywarmer
£14.63 + VAT
(£17.56 inc VAT)
4-Tex stretch 3-layer softshell bodywarmer
£44.93 + VAT
(£53.92 inc VAT)
Access insulated bodywarmer
£19.43 + VAT
(£23.32 inc VAT)
4-Tex stretch holster trousers
£67.50 + VAT
(£81.00 inc VAT)
Action shorts
£14.93 + VAT
(£17.92 inc VAT)
4-Tex stretch 3-layer softshell jacket
£52.50 + VAT
(£63.00 inc VAT)
Asgard II quilted fleece
£28.43 + VAT
(£34.12 inc VAT)
Beauford insulated jacket
£43.43 + VAT
(£52.12 inc VAT)
Classic 3-in-1 jacket
£44.93 + VAT
(£53.92 inc VAT)
Classic 65/35 polo shirt
£8.93 + VAT
(£10.72 inc VAT)