Thermostatic valve (TRV) & Manual valve (MRV) / Lockshield Valve pair. TRV+MRV Include: 1 x 15mm Thermostatic Valve + 1 x 15mm Manual Valve. TRV+Lockshield Include: 1 x 15mm Thermostatic Valve + 1 x 15mm Lockshield Valve.
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