How do you know whether you need 7" or 12"?

You need to get down and look and measure. There is no automatic answer. It depends on how your wheels are mounted together and where the valve stems are. Measure from the inside valve stem to the location where you intend to mount the other end. You want to use the shortest length possible. If you install extensions that are too long, then (in my experience) they may unthread themselves due to constant bouncing.

Manufacturer	bestautopartstool
Brand	Tiziri
Product Dimensions	30.48 x 1.27 x 1.27 cm; 408.23 g
Item model number	BAPT001
Manufacturer Part Number	BAPT001
Item Weight	408 g

Tiziri 4PCS 12" Tire Valve Stems Braided Dual Tire Valve Stem Extension Truck RV Trailer Wheel 300mm New Extender Rod

Details

Description

Specifications

Common Questions