PYREX? SPARE PTFE STOPCOCK KEY, 4.0MM T-BORE, 18.8mm DIAMETER

PYREX? SPARE PTFE STOPCOCK KEY, 4.0MM T-BORE, 18.8mm DIAMETER
 
PTFE stopcock key with silicone 'O' ring and PP retaining device
PTFE keys are fully interchangeable
Keys are self lubricating, avoiding the need for stopcock grease
Keys have a 1:10 taper to accurately fit the relevant glass stopcock barrel