Sure Stim 7100H
(Low to https://www.retrievertrainingonline.com/store/admin.php?dispatch=settings.manage§ion_id=Thumbnails&highlight=convert_tohigh power)

for dogs over 20 lbs Surestim 7000M : low to medium power for dogs over 15 lbs
The new Surestim feature assures the trainer that the stimulation has been implemented through a positive vibration feedback feature in the handheld transmitter. The 7000M is identical to its big brother the 7100H but is designed for smaller breeds or dogs that do not need a high output(Low to high power)

Features

• Low to high power.
• Rheostat dial allows for gradual increases in stimulation intensity with no jumps between levels (0-127).
• Two-dog models allow the trainer to control two different dogs from one transmitter without the hassle of handling unnecessary parts.
• dogtra 1900NCP Field Star Series has a 1/2-mile range.
• Stimulation type - Nick , Constant and nonstimulating pager/vibration.
• Surestim positive vibration feature in transmitter
• Rechargeable, user-replaceable Ni-MH batteries.

• Fully Waterproof collar/receiver and transmitter.
• Easily visible blue LCD screen displays exact level of stimulation and can be seen in the dark or low light conditions.
• Three bar battery life indicator and LED colored indicator to show remaining battery life.

Package Contents

• Transmitter
• Receiver (two collar receivers for dogtra two-dog models)
• Battery charger and splitter cable
• Test light
• Owner's manual
• Carrying case