If you are uncertain about whether you need the euro-pin or US-cup style of extension - give us a call at 727.656.6569 so we can help you get the right parts!
Chinook Aluminum Mast Extension - US Base Cup (Standard Diameter)
These Chinook extensions are the SDM version, made to fit standard diameter masts and fit a US Cup style mast foot. The aluminum alloy is lightweight and durable and the EX power-haul pulley and cleat system has oversized brass pulleys to make downhauling easier. The adjustment is via a collar and pin system and is fool-proof.
The short size gives you up to 12cm of extension, medium is up to 28cm of extension and long is up to 38cm of extension.